diff --git a/Extensions/UserScript/Return Youtube Dislike.user.js b/Extensions/UserScript/Return Youtube Dislike.user.js
index 7a728d9..41f89c6 100644
--- a/Extensions/UserScript/Return Youtube Dislike.user.js	
+++ b/Extensions/UserScript/Return Youtube Dislike.user.js	
@@ -442,7 +442,12 @@ function createVoteClient({
     return current;
   }
 
-  return { ensureRegistered, submitVote };
+  async function getRegisteredUser() {
+    const credential = await credentialStore.load();
+    return isConfirmedCredential(credential) ? { userId: credential.userId } : null;
+  }
+
+  return { ensureRegistered, getRegisteredUser, submitVote };
 }
 
 
diff --git a/Extensions/combined/_locales/en/messages.json b/Extensions/combined/_locales/en/messages.json
index 5001b5e..2a7460f 100644
--- a/Extensions/combined/_locales/en/messages.json
+++ b/Extensions/combined/_locales/en/messages.json
@@ -587,6 +587,104 @@
   "hideClutterButtonsAfter": {
     "message": "After: only Like and Dislike stay visible"
   },
+  "discussion_title": { "message": "RYD comments" },
+  "discussion_subtitle": { "message": "A community discussion hosted by Return YouTube Dislike." },
+  "discussion_independent": { "message": "These comments are separate from YouTube." },
+  "discussion_open": { "message": "Open RYD comments" },
+  "discussion_close": { "message": "Close" },
+  "discussion_new": { "message": "Newest" },
+  "discussion_top": { "message": "Top" },
+  "discussion_sort": { "message": "Sort comments" },
+  "discussion_refresh": { "message": "Refresh" },
+  "discussion_loading": { "message": "Loading comments…" },
+  "discussion_empty": { "message": "No comments yet. Start the conversation." },
+  "discussion_replyEmpty": { "message": "No replies yet." },
+  "discussion_comment": { "message": "Comment" },
+  "discussion_post": { "message": "Post comment" },
+  "discussion_reply": { "message": "Reply" },
+  "discussion_postReply": { "message": "Post reply" },
+  "discussion_cancel": { "message": "Cancel" },
+  "discussion_save": { "message": "Save" },
+  "discussion_edit": { "message": "Edit" },
+  "discussion_delete": { "message": "Delete" },
+  "discussion_deleteConfirm": { "message": "Delete this comment?" },
+  "discussion_deleted": { "message": "Comment deleted" },
+  "discussion_edited": { "message": "edited" },
+  "discussion_replies": { "message": "Replies ($1)" },
+  "discussion_more": { "message": "Load more" },
+  "discussion_like": { "message": "Like" },
+  "discussion_dislike": { "message": "Dislike" },
+  "discussion_reacting": { "message": "Saving reaction…" },
+  "discussion_signInRequired": { "message": "Sign in from the extension popup to continue." },
+  "discussion_tierRequired": { "message": "Posting is available to active Commenter members and above." },
+  "discussion_join": { "message": "Become a Commenter" },
+  "discussion_gate": { "message": "Everyone can read and react. Active Commenter members and above can post." },
+  "discussion_nicknameRequired": { "message": "Choose your public RYD nickname before posting." },
+  "discussion_nicknameLabel": { "message": "Public RYD nickname" },
+  "discussion_nicknameHint": {
+    "message": "3–32 letters, numbers, spaces, dots, dashes or underscores. This name will appear with your comments."
+  },
+  "discussion_nicknameSave": { "message": "Save nickname" },
+  "discussion_nicknameTaken": { "message": "This nickname is already taken. Choose another." },
+  "discussion_nicknameInvalid": { "message": "Use 3–32 letters, numbers, spaces, dots, dashes or underscores." },
+  "discussion_nicknameChange": { "message": "Change nickname" },
+  "discussion_as": { "message": "Commenting as $1" },
+  "discussion_placeholder": { "message": "Add to the discussion…" },
+  "discussion_characters": { "message": "$1 / $2" },
+  "discussion_report": { "message": "Report" },
+  "discussion_reportTitle": { "message": "Report comment" },
+  "discussion_reportReason": { "message": "Reason" },
+  "discussion_reportSpam": { "message": "Spam" },
+  "discussion_reportAbuse": { "message": "Harassment or hate" },
+  "discussion_reportOther": { "message": "Other" },
+  "discussion_reportDetails": { "message": "Additional details (optional)" },
+  "discussion_reportSend": { "message": "Send report" },
+  "discussion_reportDone": { "message": "Report received. Thank you." },
+  "discussion_moderation": { "message": "Moderation" },
+  "discussion_queueEmpty": { "message": "No reports to review." },
+  "discussion_hide": { "message": "Hide comment" },
+  "discussion_restore": { "message": "Restore comment" },
+  "discussion_dismiss": { "message": "Dismiss reports" },
+  "discussion_ban": { "message": "Ban author" },
+  "discussion_unban": { "message": "Unban author" },
+  "discussion_moderationReason": { "message": "Moderation reason" },
+  "discussion_moderationSaved": { "message": "Moderation action saved." },
+  "discussion_reported": { "message": "$1 reports" },
+  "discussion_unavailable": { "message": "RYD comments are unavailable for this video." },
+  "discussion_commentUnavailable": { "message": "This comment is no longer available." },
+  "discussion_error": { "message": "Unable to connect. Please try again." },
+  "discussion_rateLimited": { "message": "Please wait a moment before trying again." },
+  "discussion_conflict": { "message": "This comment changed. Refresh and try again." },
+  "discussion_forbidden": { "message": "This action is not available for your account." },
+  "discussion_retry": { "message": "Try again" },
+  "discussion_notifications": { "message": "Notifications" },
+  "discussion_notificationEmpty": { "message": "You're all caught up." },
+  "discussion_notificationReply": { "message": "$1 replied to your comment" },
+  "discussion_notificationLike": { "message": "Someone liked your comment" },
+  "discussion_notificationLikes": { "message": "Your comment received $1 likes" },
+  "discussion_notificationDislike": { "message": "Someone disliked your comment" },
+  "discussion_notificationReaction": { "message": "Someone reacted to your comment" },
+  "discussion_someone": { "message": "Someone" },
+  "discussion_markRead": { "message": "Mark read" },
+  "discussion_markAllRead": { "message": "Mark all read" },
+  "discussion_view": { "message": "View discussion" },
+  "discussion_unread": { "message": "$1 unread notifications" },
+  "discussion_signedOutInbox": { "message": "Sign in to see replies and reactions to your comments." },
+  "discussion_notificationUnavailable": { "message": "This discussion is no longer available." },
+  "discussion_discussionTab": { "message": "Discussion" },
+  "discussion_nickname": { "message": "Nickname" },
+  "discussion_reportCount": { "message": "Reports" },
+  "discussion_reportStatus": { "message": "Report status" },
+  "discussion_openReports": { "message": "Open reports" },
+  "discussion_resolvedReports": { "message": "Dismissed reports" },
+  "discussion_author": { "message": "Author" },
+  "discussion_me": { "message": "You" },
+  "discussion_saving": { "message": "Saving…" },
+  "discussion_confirm": { "message": "Confirm" },
+  "discussion_notificationUpdated": { "message": "New activity on your comments" },
+  "discussion_showThread": { "message": "Show thread" },
+  "discussion_loadReplies": { "message": "Show replies ($1)" },
+  "patreonTierCommenter": { "message": "Commenter" },
   "changelog_brand_logo_alt": {
     "message": "Return YouTube Dislike logo"
   }
diff --git a/Extensions/combined/_locales/ru/messages.json b/Extensions/combined/_locales/ru/messages.json
index 0e4ff5d..a38dfd6 100644
--- a/Extensions/combined/_locales/ru/messages.json
+++ b/Extensions/combined/_locales/ru/messages.json
@@ -566,6 +566,108 @@
   "hideClutterButtonsAfter": {
     "message": "After: only Like and Dislike stay visible"
   },
+  "discussion_title": { "message": "Комментарии RYD" },
+  "discussion_subtitle": { "message": "Обсуждение сообщества Return YouTube Dislike." },
+  "discussion_independent": { "message": "Эти комментарии не связаны с комментариями YouTube." },
+  "discussion_open": { "message": "Открыть комментарии RYD" },
+  "discussion_close": { "message": "Закрыть" },
+  "discussion_new": { "message": "Сначала новые" },
+  "discussion_top": { "message": "Популярные" },
+  "discussion_sort": { "message": "Сортировка комментариев" },
+  "discussion_refresh": { "message": "Обновить" },
+  "discussion_loading": { "message": "Загрузка комментариев…" },
+  "discussion_empty": { "message": "Комментариев пока нет. Начните обсуждение." },
+  "discussion_replyEmpty": { "message": "Ответов пока нет." },
+  "discussion_comment": { "message": "Комментарий" },
+  "discussion_post": { "message": "Отправить" },
+  "discussion_reply": { "message": "Ответить" },
+  "discussion_postReply": { "message": "Отправить ответ" },
+  "discussion_cancel": { "message": "Отмена" },
+  "discussion_save": { "message": "Сохранить" },
+  "discussion_edit": { "message": "Изменить" },
+  "discussion_delete": { "message": "Удалить" },
+  "discussion_deleteConfirm": { "message": "Удалить этот комментарий?" },
+  "discussion_deleted": { "message": "Комментарий удалён" },
+  "discussion_edited": { "message": "изменён" },
+  "discussion_replies": { "message": "Ответы ($1)" },
+  "discussion_more": { "message": "Показать ещё" },
+  "discussion_like": { "message": "Нравится" },
+  "discussion_dislike": { "message": "Не нравится" },
+  "discussion_reacting": { "message": "Сохранение реакции…" },
+  "discussion_signInRequired": { "message": "Чтобы продолжить, войдите в аккаунт через меню расширения." },
+  "discussion_tierRequired": { "message": "Писать могут участники с активным уровнем Commenter и выше." },
+  "discussion_join": { "message": "Стать участником Commenter" },
+  "discussion_gate": {
+    "message": "Читать и оценивать могут все. Писать могут участники с активным уровнем Commenter и выше."
+  },
+  "discussion_nicknameRequired": { "message": "Перед отправкой выберите публичный псевдоним RYD." },
+  "discussion_nicknameLabel": { "message": "Публичный псевдоним RYD" },
+  "discussion_nicknameHint": {
+    "message": "От 3 до 32 букв, цифр, пробелов, точек, дефисов или знаков подчёркивания. Это имя будет видно рядом с вашими комментариями."
+  },
+  "discussion_nicknameSave": { "message": "Сохранить псевдоним" },
+  "discussion_nicknameTaken": { "message": "Этот псевдоним уже занят. Выберите другой." },
+  "discussion_nicknameInvalid": {
+    "message": "Используйте от 3 до 32 букв, цифр, пробелов, точек, дефисов или знаков подчёркивания."
+  },
+  "discussion_nicknameChange": { "message": "Изменить псевдоним" },
+  "discussion_as": { "message": "Вы пишете как $1" },
+  "discussion_placeholder": { "message": "Добавьте комментарий…" },
+  "discussion_characters": { "message": "$1 / $2" },
+  "discussion_report": { "message": "Пожаловаться" },
+  "discussion_reportTitle": { "message": "Жалоба на комментарий" },
+  "discussion_reportReason": { "message": "Причина" },
+  "discussion_reportSpam": { "message": "Спам" },
+  "discussion_reportAbuse": { "message": "Оскорбления или ненависть" },
+  "discussion_reportOther": { "message": "Другое" },
+  "discussion_reportDetails": { "message": "Дополнительные сведения (необязательно)" },
+  "discussion_reportSend": { "message": "Отправить жалобу" },
+  "discussion_reportDone": { "message": "Жалоба отправлена. Спасибо." },
+  "discussion_moderation": { "message": "Модерация" },
+  "discussion_queueEmpty": { "message": "Новых жалоб нет." },
+  "discussion_hide": { "message": "Скрыть комментарий" },
+  "discussion_restore": { "message": "Восстановить комментарий" },
+  "discussion_dismiss": { "message": "Отклонить жалобы" },
+  "discussion_ban": { "message": "Заблокировать автора" },
+  "discussion_unban": { "message": "Разблокировать автора" },
+  "discussion_moderationReason": { "message": "Причина модерации" },
+  "discussion_moderationSaved": { "message": "Действие модератора сохранено." },
+  "discussion_reported": { "message": "Жалоб: $1" },
+  "discussion_unavailable": { "message": "Комментарии RYD недоступны для этого видео." },
+  "discussion_commentUnavailable": { "message": "Этот комментарий больше недоступен." },
+  "discussion_error": { "message": "Не удалось подключиться. Попробуйте ещё раз." },
+  "discussion_rateLimited": { "message": "Немного подождите и попробуйте снова." },
+  "discussion_conflict": { "message": "Комментарий изменился. Обновите страницу и попробуйте снова." },
+  "discussion_forbidden": { "message": "Это действие недоступно для вашего аккаунта." },
+  "discussion_retry": { "message": "Повторить" },
+  "discussion_notifications": { "message": "Уведомления" },
+  "discussion_notificationEmpty": { "message": "Новых уведомлений нет." },
+  "discussion_notificationReply": { "message": "$1 ответил(а) на ваш комментарий" },
+  "discussion_notificationLike": { "message": "Кому-то понравился ваш комментарий" },
+  "discussion_notificationLikes": { "message": "Новых лайков у вашего комментария: $1" },
+  "discussion_notificationDislike": { "message": "Кому-то не понравился ваш комментарий" },
+  "discussion_notificationReaction": { "message": "Кто-то оценил ваш комментарий" },
+  "discussion_someone": { "message": "Кто-то" },
+  "discussion_markRead": { "message": "Отметить прочитанным" },
+  "discussion_markAllRead": { "message": "Прочитать все" },
+  "discussion_view": { "message": "Открыть обсуждение" },
+  "discussion_unread": { "message": "Непрочитанных уведомлений: $1" },
+  "discussion_signedOutInbox": { "message": "Войдите, чтобы видеть ответы и реакции на ваши комментарии." },
+  "discussion_notificationUnavailable": { "message": "Это обсуждение больше недоступно." },
+  "discussion_discussionTab": { "message": "Обсуждение" },
+  "discussion_nickname": { "message": "Псевдоним" },
+  "discussion_reportCount": { "message": "Жалобы" },
+  "discussion_reportStatus": { "message": "Статус жалоб" },
+  "discussion_openReports": { "message": "Открытые жалобы" },
+  "discussion_resolvedReports": { "message": "Закрытые жалобы" },
+  "discussion_author": { "message": "Автор" },
+  "discussion_me": { "message": "Вы" },
+  "discussion_saving": { "message": "Сохранение…" },
+  "discussion_confirm": { "message": "Подтвердить" },
+  "discussion_notificationUpdated": { "message": "Новая активность в ваших комментариях" },
+  "discussion_showThread": { "message": "Показать ветку" },
+  "discussion_loadReplies": { "message": "Показать ответы ($1)" },
+  "patreonTierCommenter": { "message": "Commenter" },
   "changelog_brand_logo_alt": {
     "message": "Логотип Return YouTube Dislike"
   }
diff --git a/Extensions/combined/comments-bridge.js b/Extensions/combined/comments-bridge.js
new file mode 100644
index 0000000..ba15187
--- /dev/null
+++ b/Extensions/combined/comments-bridge.js
@@ -0,0 +1,138 @@
+(() => {
+  const REQUEST = "ryd-discussion-state-request";
+  const ATTRIBUTE = "data-ryd-discussion-native-state";
+  const INSTALL = Symbol.for("return-youtube-dislike.discussion-bridge");
+  if (window[INSTALL]) return;
+  window[INSTALL] = true;
+
+  function data(element) {
+    return element?.polymerController?.data || element?.data || null;
+  }
+
+  function hasDisabledNotice(value, depth = 0) {
+    if (!value || typeof value !== "object" || depth > 14) return false;
+    if (value.messageRenderer) {
+      const runs = value.messageRenderer.text?.runs || [];
+      if (
+        runs.some((run) => {
+          try {
+            const url = new URL(run.navigationEndpoint?.urlEndpoint?.url);
+            return url.hostname === "support.google.com" && url.pathname === "/youtube/answer/9706180";
+          } catch {
+            return false;
+          }
+        })
+      )
+        return true;
+    }
+    return Object.values(value).some((child) => hasDisabledNotice(child, depth + 1));
+  }
+
+  function positiveKidsFlag(value) {
+    return ["isMadeForKids", "madeForKids", "is_made_for_kids"].some((key) => value?.[key] === true);
+  }
+
+  function hasKidsMiniplayerNotice(response) {
+    const renderer = response?.playabilityStatus?.miniplayer?.miniplayerRenderer;
+    if (renderer?.playbackMode !== "PLAYBACK_MODE_PAUSED_ONLY") return false;
+    const warning = renderer.minimizedEndpoint?.openPopupAction?.popup?.notificationActionRenderer;
+    const command = warning?.actionButton?.buttonRenderer?.command;
+    return [command?.urlEndpoint?.url, command?.commandMetadata?.webCommandMetadata?.url].some((value) => {
+      if (typeof value !== "string") return false;
+      try {
+        const url = new URL(value, "https://www.youtube.com");
+        return (
+          url.protocol === "https:" &&
+          url.hostname === "support.google.com" &&
+          (url.pathname === "/youtube/answer/9632097" ||
+            (url.pathname === "/youtube/bin/answer.py" && url.searchParams.get("answer") === "9632097"))
+        );
+      } catch {
+        return false;
+      }
+    });
+  }
+
+  function isMadeForKids(root, videoId) {
+    if (
+      ["is-made-for-kids", "made-for-kids"].some(
+        (name) => root.hasAttribute(name) && root.getAttribute(name) !== "false",
+      )
+    )
+      return true;
+    const controller = root.polymerController || root;
+    const rootData = data(root);
+    if (
+      positiveKidsFlag(rootData) ||
+      ((!rootData?.videoDetails?.videoId || rootData.videoDetails.videoId === videoId) &&
+        positiveKidsFlag(rootData?.videoDetails))
+    )
+      return true;
+    const player = root.querySelector("#movie_player, #shorts-player") || document.querySelector("#shorts-player");
+    const candidates = [controller.playerData, controller.playerResponse, data(root)?.playerResponse];
+    try {
+      candidates.push(player?.getPlayerResponse?.());
+    } catch {
+      /* Player may be between videos. */
+    }
+    if (window.ytInitialPlayerResponse?.videoDetails?.videoId === videoId)
+      candidates.push(window.ytInitialPlayerResponse);
+    return candidates.some((value) => {
+      if (value?.videoDetails?.videoId !== videoId) return false;
+      const microformat = value.microformat?.playerMicroformatRenderer;
+      return (
+        positiveKidsFlag(value) ||
+        positiveKidsFlag(value.videoDetails) ||
+        hasKidsMiniplayerNotice(value) ||
+        ((!microformat?.videoId || microformat.videoId === videoId) && positiveKidsFlag(microformat))
+      );
+    });
+  }
+
+  function inspect(event) {
+    const root = event.target;
+    if (!(root instanceof Element) || !root.matches("ytd-watch-flexy, ytd-watch-grid, ytd-reel-video-renderer")) return;
+    const url = new URL(location.href);
+    const shorts = url.pathname.startsWith("/shorts/");
+    const videoId = shorts ? url.pathname.split("/")[2] : url.searchParams.get("v");
+    if (!/^[A-Za-z0-9_-]{11}$/.test(videoId || "")) return;
+    let disabled = false;
+    if (shorts) {
+      const player = document.querySelector("#shorts-player");
+      let playerId;
+      try {
+        playerId = player?.getVideoData?.()?.video_id;
+      } catch {
+        /* Player has not hydrated yet. */
+      }
+      const rootData = data(root);
+      const identity = root.getAttribute("video-id") || rootData?.videoId || rootData?.videoDetails?.videoId;
+      const linked = [...root.querySelectorAll("a[href*='/shorts/']")].some((anchor) => {
+        try {
+          return new URL(anchor.href).pathname === `/shorts/${videoId}`;
+        } catch {
+          return false;
+        }
+      });
+      const ownsCurrentPlayer = playerId === videoId && root.contains(player);
+      if (identity ? identity !== videoId : !linked && !ownsCurrentPlayer) return;
+      const actionData = data(root.querySelector("reel-action-bar-view-model"));
+      disabled = (actionData?.buttonViewModels || []).some((item) => {
+        const button = item.buttonViewModel;
+        return button?.iconName === "SHORTS_COMMENT" && button.state === "BUTTON_VIEW_MODEL_STATE_DISABLED";
+      });
+      const overlayButtons =
+        rootData?.overlay?.reelPlayerOverlayRenderer?.buttonBar?.reelActionBarViewModel?.buttonViewModels || [];
+      disabled ||= overlayButtons.some(
+        (item) =>
+          item.buttonViewModel?.iconName === "SHORTS_COMMENT" &&
+          item.buttonViewModel.state === "BUTTON_VIEW_MODEL_STATE_DISABLED",
+      );
+    } else {
+      if (url.pathname !== "/watch" || root.getAttribute("video-id") !== videoId) return;
+      disabled = [...root.querySelectorAll("ytd-comments")].some((comments) => hasDisabledNotice(data(comments)));
+    }
+    root.setAttribute(ATTRIBUTE, JSON.stringify({ videoId, disabled, madeForKids: isMadeForKids(root, videoId) }));
+  }
+  document.addEventListener(REQUEST, inspect, true);
+})();
diff --git a/Extensions/combined/content-style.css b/Extensions/combined/content-style.css
index 784275c..fb272a1 100644
--- a/Extensions/combined/content-style.css
+++ b/Extensions/combined/content-style.css
@@ -9,6 +9,478 @@
   --yt-spec-brand-background-secondary: #000 !important; */
 }
 
+.ryd-discussion,
+.ryd-discussion-popup,
+.ryd-discussion-toast {
+  --ryd-discussion-bg: var(--yt-spec-base-background, #fff);
+  --ryd-discussion-fg: var(--yt-spec-text-primary, #0f0f0f);
+  --ryd-discussion-muted: var(--yt-spec-text-secondary, #606060);
+  --ryd-discussion-surface: var(--yt-spec-badge-chip-background, #f2f2f2);
+  --ryd-discussion-line: var(--yt-spec-10-percent-layer, #dedede);
+  --ryd-discussion-accent: var(--yt-spec-call-to-action, #065fd4);
+  --ryd-discussion-on-accent: var(--yt-spec-inverted-text-primary, #fff);
+  color-scheme: light;
+  box-sizing: border-box;
+  color: var(--ryd-discussion-fg);
+  font:
+    14px/1.5 Roboto,
+    Arial,
+    sans-serif;
+  text-align: start;
+}
+
+html[dark] .ryd-discussion,
+html[dark] .ryd-discussion-popup,
+html[dark] .ryd-discussion-toast {
+  --ryd-discussion-bg: var(--yt-spec-base-background, #0f0f0f);
+  --ryd-discussion-fg: var(--yt-spec-text-primary, #f1f1f1);
+  --ryd-discussion-muted: var(--yt-spec-text-secondary, #aaa);
+  --ryd-discussion-surface: var(--yt-spec-badge-chip-background, #272727);
+  --ryd-discussion-line: var(--yt-spec-10-percent-layer, #3f3f3f);
+  --ryd-discussion-accent: var(--yt-spec-call-to-action, #3ea6ff);
+  --ryd-discussion-on-accent: var(--yt-spec-inverted-text-primary, #0f0f0f);
+  color-scheme: dark;
+}
+
+.ryd-discussion *,
+.ryd-discussion-popup *,
+.ryd-discussion-toast * {
+  box-sizing: border-box;
+}
+.ryd-discussion [hidden],
+.ryd-discussion[hidden],
+.ryd-discussion-popup [hidden],
+.ryd-discussion-backdrop[hidden] {
+  display: none !important;
+}
+.ryd-discussion {
+  width: 100%;
+  margin: 20px 0 32px;
+  padding: 20px 0;
+  border-top: 1px solid var(--ryd-discussion-line);
+}
+.ryd-discussion-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: 12px;
+}
+.ryd-discussion-brand,
+.ryd-discussion-header-actions,
+.ryd-discussion-toolbar,
+.ryd-discussion-form-actions,
+.ryd-discussion-comment-actions,
+.ryd-discussion-account,
+.ryd-discussion-comment-heading {
+  display: flex;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: 8px;
+}
+.ryd-discussion-header-actions {
+  gap: 2px;
+}
+.ryd-discussion-title {
+  margin: 0;
+  font-size: 20px;
+  font-weight: 600;
+  line-height: 1.3;
+}
+.ryd-discussion-logo {
+  padding: 4px 6px;
+  background: #d92323;
+  color: #fff;
+  font-size: 10px;
+  font-weight: 800;
+  border-radius: 6px;
+  letter-spacing: -0.2px;
+}
+.ryd-discussion-description {
+  margin: 10px 0 0;
+  color: var(--ryd-discussion-muted);
+  font-size: 13px;
+}
+.ryd-discussion-independent {
+  margin: 2px 0 20px;
+  color: var(--ryd-discussion-muted);
+  font-size: 12px;
+}
+.ryd-discussion-subtitle {
+  margin: 0;
+  font-size: 16px;
+  font-weight: 600;
+}
+.ryd-discussion-button,
+.ryd-discussion-close {
+  appearance: none;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  gap: 5px;
+  border: 0;
+  border-radius: 18px;
+  background: transparent;
+  color: inherit;
+  min-height: 34px;
+  padding: 6px 12px;
+  font: inherit;
+  font-size: 12px;
+  font-weight: 500;
+  line-height: 1.4;
+  cursor: pointer;
+  text-decoration: none;
+  white-space: normal;
+}
+.ryd-discussion-button:hover,
+.ryd-discussion-close:hover {
+  background: var(--ryd-discussion-surface);
+}
+.ryd-discussion-button[aria-pressed="true"] {
+  background: var(--ryd-discussion-surface);
+  color: var(--ryd-discussion-accent);
+}
+.ryd-discussion-button:disabled {
+  opacity: 0.5;
+  cursor: default;
+}
+.ryd-discussion-button:focus-visible,
+.ryd-discussion-close:focus-visible,
+.ryd-discussion-select:focus-visible,
+.ryd-discussion-textarea:focus-visible,
+.ryd-discussion-input:focus-visible,
+.ryd-discussion-launcher:focus-visible,
+.ryd-discussion-notification-link:focus-visible {
+  outline: 2px solid var(--ryd-discussion-accent);
+  outline-offset: 2px;
+}
+.ryd-discussion-primary {
+  background: var(--ryd-discussion-accent);
+  color: var(--ryd-discussion-on-accent);
+  padding-inline: 16px;
+}
+.ryd-discussion-primary:hover {
+  background: var(--ryd-discussion-accent);
+  filter: brightness(0.92);
+}
+.ryd-discussion-danger {
+  color: #dc3232;
+}
+.ryd-discussion-close {
+  font-size: 26px;
+  padding: 0;
+  height: 36px;
+  width: 36px;
+  min-width: 36px;
+}
+.ryd-discussion-composer {
+  margin-bottom: 20px;
+}
+.ryd-discussion-gate {
+  margin: 0 0 6px;
+  color: var(--ryd-discussion-muted);
+  font-size: 13px;
+}
+.ryd-discussion-link,
+.ryd-discussion-notification-link {
+  color: var(--ryd-discussion-accent);
+  text-decoration: none;
+}
+.ryd-discussion-link:hover,
+.ryd-discussion-notification-link:hover {
+  text-decoration: underline;
+}
+.ryd-discussion-form {
+  margin: 10px 0;
+  width: 100%;
+}
+.ryd-discussion-label {
+  display: block;
+  width: 100%;
+  color: var(--ryd-discussion-fg);
+  font-size: 13px;
+  margin: 6px 0;
+}
+.ryd-discussion-textarea,
+.ryd-discussion-input {
+  display: block;
+  width: 100%;
+  max-width: 100%;
+  min-width: 0;
+  margin-top: 6px;
+  border: 1px solid var(--ryd-discussion-line);
+  border-radius: 10px;
+  background: var(--ryd-discussion-bg);
+  color: var(--ryd-discussion-fg);
+  padding: 10px 12px;
+  font: inherit;
+  line-height: 1.5;
+}
+.ryd-discussion-textarea {
+  resize: vertical;
+  min-height: 78px;
+}
+.ryd-discussion-input {
+  max-width: 420px;
+}
+.ryd-discussion-textarea::placeholder {
+  color: var(--ryd-discussion-muted);
+}
+.ryd-discussion-form-actions {
+  justify-content: flex-end;
+  margin-top: 6px;
+}
+.ryd-discussion-counter {
+  margin-inline-end: auto;
+  color: var(--ryd-discussion-muted);
+  font-size: 11px;
+}
+.ryd-discussion-toolbar {
+  justify-content: space-between;
+  margin: 16px 0 12px;
+}
+.ryd-discussion-select {
+  border: 0;
+  border-radius: 8px;
+  padding: 8px 28px 8px 10px;
+  background: var(--ryd-discussion-surface);
+  color: inherit;
+  font: inherit;
+  font-size: 13px;
+}
+.ryd-discussion-status {
+  margin: 8px 0;
+  color: var(--ryd-discussion-muted);
+  font-size: 13px;
+}
+.ryd-discussion-status:empty {
+  display: none;
+}
+.ryd-discussion-comment {
+  padding: 16px 0;
+  border-bottom: 1px solid var(--ryd-discussion-line);
+  min-width: 0;
+}
+.ryd-discussion-comment:last-child {
+  border-bottom: 0;
+}
+.ryd-discussion-comment-heading {
+  gap: 8px;
+}
+.ryd-discussion-author {
+  font-size: 13px;
+  font-weight: 600;
+  overflow-wrap: anywhere;
+}
+.ryd-discussion-avatar {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  width: 28px;
+  height: 28px;
+  min-width: 28px;
+  border-radius: 50%;
+  color: var(--ryd-discussion-muted);
+  background: var(--ryd-discussion-surface);
+  font-size: 13px;
+  font-weight: 500;
+}
+.ryd-discussion-meta {
+  color: var(--ryd-discussion-muted);
+  font-size: 11px;
+}
+.ryd-discussion-comment-text {
+  margin: 8px 0 6px;
+  white-space: pre-wrap;
+  overflow-wrap: anywhere;
+  word-break: normal;
+  font-size: 14px;
+  line-height: 1.55;
+}
+.ryd-discussion-comment-actions {
+  gap: 2px;
+}
+.ryd-discussion-comment-actions .ryd-discussion-button {
+  padding-inline: 9px;
+}
+.ryd-discussion-thumb {
+  width: 18px;
+  height: 18px;
+  fill: currentColor;
+  flex-shrink: 0;
+}
+.ryd-discussion-thumb.is-down {
+  transform: rotate(180deg);
+}
+.ryd-discussion-reaction {
+  min-width: 42px;
+  font-variant-numeric: tabular-nums;
+}
+.ryd-discussion-replies {
+  margin-inline-start: 24px;
+  padding-inline-start: 12px;
+  border-inline-start: 2px solid var(--ryd-discussion-line);
+}
+.ryd-discussion-replies:empty {
+  display: none;
+}
+.ryd-discussion-reply {
+  padding-block: 12px;
+}
+.ryd-discussion-inline-editor:empty {
+  display: none;
+}
+.ryd-discussion-confirm {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  margin: 12px 0;
+  flex-wrap: wrap;
+}
+.ryd-discussion-more {
+  margin: 12px 0;
+  background: var(--ryd-discussion-surface);
+}
+.ryd-discussion-comment.is-highlighted {
+  border-radius: 10px;
+  padding-inline: 12px;
+  background: var(--ryd-discussion-surface);
+}
+.ryd-discussion-report {
+  border: 1px solid var(--ryd-discussion-line);
+  border-radius: 12px;
+  padding: 14px;
+  margin-top: 14px;
+}
+.ryd-discussion-report-reason {
+  color: var(--ryd-discussion-muted);
+  font-size: 12px;
+  white-space: pre-wrap;
+  overflow-wrap: anywhere;
+}
+.ryd-discussion-notification {
+  border-bottom: 1px solid var(--ryd-discussion-line);
+  padding: 12px 8px;
+  display: flex;
+  align-items: flex-start;
+  gap: 8px;
+  flex-wrap: wrap;
+}
+.ryd-discussion-notification.is-unread {
+  background: var(--ryd-discussion-surface);
+  border-radius: 8px;
+}
+.ryd-discussion-notification-link {
+  flex: 1 1 100%;
+  font-size: 13px;
+  overflow-wrap: anywhere;
+}
+.ryd-discussion-inbox-list {
+  display: grid;
+  gap: 4px;
+}
+.ryd-discussion-launcher {
+  display: block;
+  margin: 8px auto;
+  width: 48px;
+  height: 48px;
+  border: 1px solid rgba(255, 255, 255, 0.35);
+  border-radius: 50%;
+  background: #d92323;
+  color: #fff;
+  font:
+    700 12px/1 Roboto,
+    Arial,
+    sans-serif;
+  cursor: pointer;
+  box-shadow: 0 2px 8px #0003;
+}
+.ryd-discussion-backdrop {
+  position: fixed;
+  inset: 0;
+  background: #0008;
+  z-index: 2147483000;
+}
+.ryd-discussion-shorts {
+  position: fixed;
+  inset: 0 0 0 auto;
+  width: min(440px, 100vw);
+  height: 100dvh;
+  margin: 0;
+  padding: 20px;
+  background: var(--ryd-discussion-bg);
+  z-index: 2147483001;
+  border: 0;
+  box-shadow: -8px 0 32px #0003;
+  overflow-y: auto;
+  overscroll-behavior: contain;
+}
+.ryd-discussion-shorts .ryd-discussion-header {
+  align-items: flex-start;
+}
+.ryd-discussion-shorts .ryd-discussion-header-actions {
+  width: 100%;
+}
+.ryd-discussion-shorts .ryd-discussion-close {
+  margin-inline-start: auto;
+}
+.ryd-discussion-toast {
+  position: fixed;
+  inset-inline-end: 24px;
+  bottom: 24px;
+  z-index: 2147483002;
+  width: min(360px, calc(100vw - 32px));
+  display: flex;
+  gap: 12px;
+  align-items: flex-start;
+  padding: 16px;
+  border-radius: 14px;
+  background: var(--ryd-discussion-bg);
+  border: 1px solid var(--ryd-discussion-line);
+  box-shadow: 0 6px 30px #0003;
+}
+.ryd-discussion-toast p {
+  margin: 5px 0;
+  font-size: 13px;
+}
+.ryd-discussion-toast .ryd-discussion-close {
+  margin-inline-start: auto;
+}
+.ryd-discussion-sr-only {
+  position: absolute;
+  width: 1px;
+  height: 1px;
+  padding: 0;
+  overflow: hidden;
+  clip: rect(0, 0, 0, 0);
+  white-space: nowrap;
+  border: 0;
+}
+@media (max-width: 600px) {
+  #ryd-discussion-panel {
+    max-inline-size: calc(100vw - 48px);
+    margin-inline: auto;
+  }
+  .ryd-discussion-header-actions {
+    width: 100%;
+  }
+  .ryd-discussion-title {
+    font-size: 18px;
+  }
+  .ryd-discussion-replies {
+    margin-inline-start: 10px;
+    padding-inline-start: 8px;
+  }
+  .ryd-discussion-shorts {
+    width: 100vw;
+    padding: 16px;
+  }
+  .ryd-discussion-toast {
+    inset-inline-end: 16px;
+    bottom: 16px;
+  }
+}
+
 /* html:not(.style-scope)[dark], :not(.style-scope)[dark] {
   --yt-spec-general-background-a: #000 !important;
   --yt-spec-general-background-b: #000 !important;
diff --git a/Extensions/combined/manifest-chrome.json b/Extensions/combined/manifest-chrome.json
index fcf4a7a..8f7688b 100644
--- a/Extensions/combined/manifest-chrome.json
+++ b/Extensions/combined/manifest-chrome.json
@@ -11,55 +11,32 @@
     "48": "icons/icon48.png",
     "128": "icons/icon128.png"
   },
-  "host_permissions": [
-    "*://*.youtube.com/*",
-    "*://returnyoutubedislikeapi.com/*"
-  ],
-  "permissions": [
-    "storage"
-  ],
-  "optional_permissions": [
-    "identity"
-  ],
+  "host_permissions": ["*://*.youtube.com/*", "*://returnyoutubedislikeapi.com/*"],
+  "permissions": ["storage", "alarms"],
+  "optional_permissions": ["identity"],
   "action": {
     "default_popup": "popup.html"
   },
   "content_scripts": [
     {
-      "matches": [
-        "*://youtube.com/*",
-        "*://www.youtube.com/*",
-        "*://m.youtube.com/*"
-      ],
-      "exclude_matches": [
-        "*://*.music.youtube.com/*"
-      ],
-      "js": [
-        "ryd.content-script.js"
-      ],
-      "css": [
-        "content-style.css"
-      ]
+      "matches": ["*://youtube.com/*", "*://www.youtube.com/*", "*://m.youtube.com/*"],
+      "exclude_matches": ["*://*.music.youtube.com/*"],
+      "js": ["ryd.content-script.js"],
+      "css": ["content-style.css"]
     }
   ],
   "externally_connectable": {
-    "matches": [
-      "*://*.youtube.com/*"
-    ]
+    "matches": ["*://*.youtube.com/*"]
   },
   "web_accessible_resources": [
     {
-      "resources": [
-        "ryd.script.js",
-        "menu-fixer.js"
-      ],
-      "matches": [
-        "*://*.youtube.com/*"
-      ]
+      "resources": ["ryd.script.js", "menu-fixer.js", "comments-bridge.js"],
+      "matches": ["*://*.youtube.com/*"]
     }
   ],
   "options_ui": {
     "page": "popup.html",
     "open_in_tab": false
-  }
+  },
+  "minimum_chrome_version": "116"
 }
diff --git a/Extensions/combined/manifest-firefox.json b/Extensions/combined/manifest-firefox.json
index dc33aee..503c179 100644
--- a/Extensions/combined/manifest-firefox.json
+++ b/Extensions/combined/manifest-firefox.json
@@ -12,7 +12,14 @@
     "48": "icons/icon48.png",
     "128": "icons/icon128.png"
   },
-  "permissions": ["activeTab", "*://*.youtube.com/*", "storage", "*://returnyoutubedislikeapi.com/*", "identity"],
+  "permissions": [
+    "activeTab",
+    "*://*.youtube.com/*",
+    "storage",
+    "*://returnyoutubedislikeapi.com/*",
+    "identity",
+    "alarms"
+  ],
   "browser_specific_settings": {
     "gecko": {
       "id": "{762f9885-5a13-4abd-9c77-433dcd38b8fd}",
@@ -23,7 +30,6 @@
       }
     }
   },
-
   "browser_action": {
     "default_popup": "popup.html"
   },
@@ -40,5 +46,5 @@
     "page": "popup.html",
     "open_in_tab": false
   },
-  "web_accessible_resources": ["menu-fixer.js"]
+  "web_accessible_resources": ["menu-fixer.js", "comments-bridge.js"]
 }
diff --git a/Extensions/combined/manifest-safari.json b/Extensions/combined/manifest-safari.json
index f6ca020..06f066c 100644
--- a/Extensions/combined/manifest-safari.json
+++ b/Extensions/combined/manifest-safari.json
@@ -12,7 +12,7 @@
     "48": "icons/icon48.png",
     "128": "icons/icon128.png"
   },
-  "permissions": ["activeTab", "*://*.youtube.com/*", "storage", "*://returnyoutubedislikeapi.com/*"],
+  "permissions": ["activeTab", "*://*.youtube.com/*", "storage", "*://returnyoutubedislikeapi.com/*", "alarms"],
   "browser_action": {
     "default_popup": "popup.html"
   },
@@ -28,5 +28,5 @@
   "options_ui": {
     "page": "popup.html"
   },
-  "web_accessible_resources": ["menu-fixer.js"]
+  "web_accessible_resources": ["menu-fixer.js", "comments-bridge.js"]
 }
diff --git a/Extensions/combined/popup.css b/Extensions/combined/popup.css
index e8fcb65..0eba8de 100644
--- a/Extensions/combined/popup.css
+++ b/Extensions/combined/popup.css
@@ -13,6 +13,26 @@
 }
 
 /***   MATERIAL 3   ***/
+.ryd-discussion-popup {
+  --yt-spec-base-background: var(--background);
+  --yt-spec-text-primary: #f5eded;
+  --yt-spec-text-secondary: #ccbebe;
+  --yt-spec-badge-chip-background: var(--tertiary);
+  --yt-spec-10-percent-layer: #624d4d;
+  --yt-spec-call-to-action: var(--primary);
+  margin: 0;
+  width: 100%;
+}
+.ryd-discussion-popup .ryd-discussion-inbox {
+  margin-top: 12px;
+  padding: 0 8px 12px;
+  max-height: 400px;
+  overflow-y: auto;
+}
+.ryd-discussion-popup .ryd-discussion-toolbar {
+  justify-content: flex-start;
+}
+
 .m3-primary {
   background: var(--primary) !important;
   color: var(--background) !important;
diff --git a/Extensions/combined/popup.html b/Extensions/combined/popup.html
index 68f9c72..a37d6a8 100644
--- a/Extensions/combined/popup.html
+++ b/Extensions/combined/popup.html
@@ -5,6 +5,7 @@
     <meta content="text/html; charset=utf-8" />
     <title title="__MSG_extensionName__">__MSG_extensionName__</title>
     <link rel="stylesheet" href="popup.css" />
+    <link rel="stylesheet" href="content-style.css" />
   </head>
   <!--   END HEADER -->
   <body>
@@ -85,9 +86,19 @@
       <button class="m3-btn" id="link_github" title="__MSG_linkGithub__">__MSG_linkGithub__</button>
       <button class="m3-btn" style="margin-top: 0.3em" id="link_help" title="__MSG_linkHelp__">__MSG_linkHelp__</button>
       <br />
+      <button
+        type="button"
+        id="ryd-discussion-inbox-toggle"
+        class="m3-btn"
+        aria-expanded="false"
+        aria-controls="ryd-discussion-popup"
+      >
+        __MSG_discussion_notifications__
+      </button>
       <button class="m3-btn" style="margin-top: 0.3em" id="link_changelog" title="__MSG_linkChangelog__">
         __MSG_linkChangelog__
       </button>
+      <section id="ryd-discussion-popup" class="ryd-discussion-popup"></section>
 
       <br />
       <br />
diff --git a/Extensions/combined/popup.js b/Extensions/combined/popup.js
index 1faf6d8..bbc0525 100644
--- a/Extensions/combined/popup.js
+++ b/Extensions/combined/popup.js
@@ -1,5 +1,6 @@
 import { config as appConfig, getApiUrl, getApiEndpoint } from "./src/config.js";
 import { getGitHubLoginErrorMessage } from "./src/github-login-error";
+import { initDiscussionPopup } from "./src/discussion/popup";
 import {
   hasAuthenticationDataPermission,
   onAuthenticationDataPermissionRemoved,
@@ -47,6 +48,7 @@ function localizeHtmlPage() {
 }
 
 localizeHtmlPage();
+initDiscussionPopup();
 
 /*   Links   */
 createLink(config.links.website, "link_website");
@@ -195,6 +197,7 @@ function initPatreonAuth() {
 
     const tierLabels = {
       premium: chrome.i18n.getMessage("patreonTierPremium"),
+      commenter: chrome.i18n.getMessage("patreonTierCommenter"),
       supporter: chrome.i18n.getMessage("patreonTierSupporter"),
       basic: chrome.i18n.getMessage("patreonTierBasic"),
       none: chrome.i18n.getMessage("patreonTierNone"),
diff --git a/Extensions/combined/ryd.background.js b/Extensions/combined/ryd.background.js
index e5ae7e8..8f4f261 100644
--- a/Extensions/combined/ryd.background.js
+++ b/Extensions/combined/ryd.background.js
@@ -2,6 +2,7 @@ import { config, getApiUrl, getApiEndpoint, getChangelogUrl } from "./src/config
 import { createVoteClient } from "../common/vote-client";
 import { createBrowserCredentialStore } from "./src/vote-client-adapter";
 import { loginWithGitHub } from "./src/github-auth";
+import { createDiscussionBackground } from "./src/discussion-background";
 import {
   hasAuthenticationDataPermission,
   onAuthenticationDataPermissionRemoved,
@@ -38,6 +39,14 @@ const voteClient = createVoteClient({
   cryptoImpl: globalThis.crypto,
 });
 
+const discussionBackground = createDiscussionBackground({
+  api,
+  voteClient,
+  hasConsent: async () =>
+    !usesFirefoxDataCollectionConsent() || (await hasAuthenticationDataPermission({ queryBackground: false })),
+});
+discussionBackground.initialize();
+
 initExtConfig();
 voteClient.ensureRegistered().catch((error) => console.error("Vote registration failed", error));
 
@@ -130,11 +139,15 @@ function queueAccountStorageMutation(operation) {
 
 function clearPatreonAuth(done) {
   const generation = ++authenticationGeneration;
+  discussionBackground.clearSession(true);
   broadcastPatreonStatus(false, null, null, generation);
   queueAccountStorageMutation((complete) => {
     chrome.storage.sync.remove(["patreonAuthenticated", "patreonUser", "patreonSessionToken"], complete);
   })
-    .then(() => done?.())
+    .then(() => {
+      discussionBackground.resumeSession().catch(() => {});
+      done?.();
+    })
     .catch((error) => console.error("Account session cleanup failed", error));
 }
 
@@ -192,7 +205,10 @@ function extractOAuthParams(responseUrl) {
 }
 
 api.runtime.onMessage.addListener((request, sender, sendResponse) => {
-  if (request.message === "patreon_logout") {
+  if (request?.message === "ryd_discussion") {
+    discussionBackground.handleMessage(request, sender).then(sendResponse);
+    return true;
+  } else if (request.message === "patreon_logout") {
     clearPatreonAuth();
   } else if (request.message === "ryd_has_authentication_consent") {
     hasAuthenticationDataPermission({ queryBackground: false }).then((granted) => sendResponse({ granted }));
@@ -573,6 +589,7 @@ const sentIds = new Set();
 let toSend = [];
 
 function storageChangeHandler(changes, area) {
+  discussionBackground.onStorageChanged(changes, area);
   if (changes.disableVoteSubmission !== undefined) {
     handleDisableVoteSubmissionChangeEvent(changes.disableVoteSubmission.newValue);
   }
diff --git a/Extensions/combined/ryd.background.spec.js b/Extensions/combined/ryd.background.spec.js
index 73204e5..1362987 100644
--- a/Extensions/combined/ryd.background.spec.js
+++ b/Extensions/combined/ryd.background.spec.js
@@ -189,7 +189,17 @@ describe("background account consent lifecycle", () => {
       await flushPromises();
       expect(stored).toEqual({});
       expect(chrome.storage.sync.remove).toHaveBeenCalledTimes(1);
-      expect(chrome.tabs.sendMessage.mock.calls.every(([, message]) => message.authenticated === false)).toBe(true);
+      expect(
+        chrome.tabs.sendMessage.mock.calls
+          .filter(([, message]) => message.message === "patreon_status_changed")
+          .every(([, message]) => message.authenticated === false),
+      ).toBe(true);
+      expect(
+        chrome.tabs.sendMessage.mock.calls
+          .filter(([, message]) => message.message === "ryd_discussion_event" && message.type === "session")
+          .every(([, message]) => message.data.authenticated === false),
+      ).toBe(true);
+
       expect(response).toHaveBeenCalledWith(expect.objectContaining({ success: false }));
     },
   );
diff --git a/Extensions/combined/ryd.content-script.js b/Extensions/combined/ryd.content-script.js
index 5fa1a23..a7ceb7a 100644
--- a/Extensions/combined/ryd.content-script.js
+++ b/Extensions/combined/ryd.content-script.js
@@ -31,6 +31,7 @@ import {
   reactionControlsCanInitialize,
 } from "./src/initialization-cycle";
 import { initPatreonFeatures } from "./src/patreon";
+import { initDiscussion } from "./src/discussion";
 import { cancelObsoleteVoteDataRequests, clearVoteDataRequestCache } from "./src/vote-data-request";
 import {
   actionBarHasHydratedData,
@@ -94,6 +95,7 @@ const pageWorldHelpersReady = injectPageWorldHelpers();
 await initExtConfig();
 await pageWorldHelpersReady;
 initPatreonFeatures();
+initDiscussion();
 
 // Settings that affect page-world helpers must continue to update even when
 // YouTube's reaction controls have not finished initializing.
diff --git a/Extensions/combined/src/discussion-background.js b/Extensions/combined/src/discussion-background.js
new file mode 100644
index 0000000..12bfac6
--- /dev/null
+++ b/Extensions/combined/src/discussion-background.js
@@ -0,0 +1,785 @@
+import { HubConnectionBuilder, HttpTransportType, LogLevel } from "@microsoft/signalr";
+import { createVoteClient, solvePuzzle } from "../../common/vote-client";
+import { discussionConfig } from "./discussion-config";
+
+const ANONYMOUS_SESSION = Object.freeze({
+  authenticated: false,
+  profile: null,
+  canPost: false,
+  isModerator: false,
+  membershipTier: "none",
+});
+const RECONNECT_ALARM = "ryd-discussion-reconnect";
+const UUID = /^[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
+const VIDEO_ID = /^[a-zA-Z0-9_-]{11}$/;
+const VIDEO_OPERATIONS = new Set([
+  "comments",
+  "replies",
+  "comment",
+  "createComment",
+  "editComment",
+  "deleteComment",
+  "react",
+  "report",
+]);
+const OPERATIONS = {
+  cancelScope: [],
+  capabilities: [],
+  session: [],
+  profile: ["nickname"],
+  comments: ["videoId", "sort", "cursor"],
+  replies: ["rootId", "cursor"],
+  comment: ["id"],
+  createComment: ["videoId", "text", "parentId", "replyToId", "requestId"],
+  editComment: ["id", "text"],
+  deleteComment: ["id"],
+  react: ["id", "value"],
+  report: ["id", "reason"],
+  reports: ["cursor", "status"],
+  dismissReport: ["id", "reason"],
+  moderateComment: ["id", "hidden", "reason"],
+  suspendProfile: ["id", "suspended", "reason"],
+  notifications: ["cursor"],
+  readNotifications: ["ids", "all"],
+};
+
+class DiscussionError extends Error {
+  constructor(code, message = code, status = 0) {
+    super(message);
+    this.code = code;
+    this.status = status;
+  }
+}
+
+function callBrowser(api, target, method, ...args) {
+  return new Promise((resolve, reject) => {
+    if (typeof target?.[method] !== "function") return resolve(undefined);
+    const callback = (value) =>
+      api.runtime?.lastError ? reject(new Error(api.runtime.lastError.message)) : resolve(value);
+    try {
+      const result = target[method](...args, callback);
+      if (result?.then) result.then(resolve, reject);
+    } catch (error) {
+      try {
+        Promise.resolve(target[method](...args)).then(resolve, reject);
+      } catch (_) {
+        reject(error);
+      }
+    }
+  });
+}
+
+function isYouTubePage(url) {
+  try {
+    const parsed = new URL(url);
+    return (
+      parsed.protocol === "https:" &&
+      parsed.hostname === "www.youtube.com" &&
+      (parsed.pathname === "/watch" || /^\/shorts\/[a-zA-Z0-9_-]{11}\/?$/.test(parsed.pathname))
+    );
+  } catch (_) {
+    return false;
+  }
+}
+
+function validateRequest(api, request, sender) {
+  if (sender?.id !== api.runtime.id) throw new DiscussionError("invalid_sender");
+  const extensionUrl = api.runtime.getURL?.("");
+  const ownPage = extensionUrl && typeof sender.url === "string" && sender.url.startsWith(extensionUrl);
+  const videoPage = sender.frameId === 0 && isYouTubePage(sender.url) && isYouTubePage(sender.tab?.url);
+  const operation = request?.operation;
+  const cancellationPage =
+    operation === "cancelScope" &&
+    sender.frameId === 0 &&
+    [sender.url, sender.tab?.url].every((value) => {
+      try {
+        return new URL(value).origin === "https://www.youtube.com";
+      } catch (_) {
+        return false;
+      }
+    });
+  if (!ownPage && !videoPage && !cancellationPage) throw new DiscussionError("invalid_sender");
+  const fields = Object.hasOwn(OPERATIONS, operation) ? OPERATIONS[operation] : null;
+  const payload = request.payload ?? {};
+  if (
+    !fields ||
+    !payload ||
+    typeof payload !== "object" ||
+    Array.isArray(payload) ||
+    Object.keys(payload).some((key) => !fields.includes(key))
+  )
+    throw new DiscussionError("invalid_request");
+  for (const key of ["id", "rootId", "parentId", "replyToId", "requestId"]) {
+    if (payload[key] != null && (typeof payload[key] !== "string" || !UUID.test(payload[key])))
+      throw new DiscussionError("invalid_request");
+  }
+  if (fields.includes("id") && !UUID.test(payload.id || "")) throw new DiscussionError("invalid_request");
+  if (fields.includes("rootId") && !UUID.test(payload.rootId || "")) throw new DiscussionError("invalid_request");
+  if (fields.includes("videoId") && !VIDEO_ID.test(payload.videoId || "")) throw new DiscussionError("invalid_request");
+  if (operation === "createComment" && !UUID.test(payload.requestId || ""))
+    throw new DiscussionError("invalid_request");
+  for (const [key, max] of [
+    ["text", 2000],
+    ["nickname", 32],
+    ["reason", 1000],
+    ["cursor", 2048],
+  ]) {
+    if (payload[key] != null && (typeof payload[key] !== "string" || payload[key].length > max))
+      throw new DiscussionError("invalid_request");
+  }
+  if (fields.includes("text") && !payload.text?.trim()) throw new DiscussionError("invalid_request");
+  if (operation === "profile" && (typeof payload.nickname !== "string" || payload.nickname.trim().length < 3))
+    throw new DiscussionError("invalid_request");
+  if (operation === "report" && !payload.reason?.trim()) throw new DiscussionError("invalid_request");
+  if (payload.sort != null && !["top", "new"].includes(payload.sort)) throw new DiscussionError("invalid_request");
+  if (payload.status != null && !["open", "resolved"].includes(payload.status))
+    throw new DiscussionError("invalid_request");
+  if (operation === "react" && ![-1, 0, 1].includes(payload.value)) throw new DiscussionError("invalid_request");
+  for (const key of ["hidden", "suspended"]) {
+    if (fields.includes(key) && typeof payload[key] !== "boolean") throw new DiscussionError("invalid_request");
+  }
+  if (
+    operation === "readNotifications" &&
+    !(payload.all === true && payload.ids == null) &&
+    !(
+      payload.all == null &&
+      Array.isArray(payload.ids) &&
+      payload.ids.length > 0 &&
+      payload.ids.length <= 100 &&
+      payload.ids.every((id) => typeof id === "string" && UUID.test(id))
+    )
+  )
+    throw new DiscussionError("invalid_request");
+  const scope = request.scope;
+  if (scope != null) {
+    if (
+      !scope ||
+      typeof scope !== "object" ||
+      Array.isArray(scope) ||
+      Object.keys(scope).some((key) => !["id", "videoId"].includes(key)) ||
+      typeof scope.id !== "string" ||
+      !UUID.test(scope.id) ||
+      typeof scope.videoId !== "string" ||
+      !VIDEO_ID.test(scope.videoId) ||
+      !Number.isInteger(sender.tab?.id) ||
+      (!videoPage && !cancellationPage) ||
+      (!VIDEO_OPERATIONS.has(operation) && operation !== "cancelScope")
+    )
+      throw new DiscussionError("invalid_scope");
+    if (operation !== "cancelScope") {
+      const current = new URL(sender.tab.url);
+      const videoId = current.pathname === "/watch" ? current.searchParams.get("v") : current.pathname.split("/")[2];
+      if (scope.videoId !== videoId || (payload.videoId && payload.videoId !== scope.videoId))
+        throw new DiscussionError("navigation_changed");
+    }
+  } else if (operation === "cancelScope" || (videoPage && VIDEO_OPERATIONS.has(operation))) {
+    throw new DiscussionError("scope_required");
+  }
+  return { operation, payload, scope };
+}
+
+function safeSession(data) {
+  const profile = data.profile;
+  return {
+    authenticated: data.authenticated === true,
+    profile: profile ? { id: profile.id, nickname: profile.nickname, suspended: profile.suspended === true } : null,
+    canPost: data.canPost === true,
+    isModerator: data.isModerator === true,
+    membershipTier: ["none", "supporter", "commenter", "premium"].includes(data.membershipTier)
+      ? data.membershipTier
+      : "none",
+  };
+}
+
+function createConnection(url, accessTokenFactory) {
+  return new HubConnectionBuilder()
+    .withUrl(url, { transport: HttpTransportType.WebSockets, skipNegotiation: true, accessTokenFactory })
+    .withAutomaticReconnect([0, 2000, 10000, 30000])
+    .withKeepAliveInterval(15000)
+    .withServerTimeout(45000)
+    .configureLogging(LogLevel.None)
+    .build();
+}
+
+export function createDiscussionBackground({
+  api,
+  voteClient,
+  fetchImpl = (...args) => fetch(...args),
+  hasConsent = async () => true,
+  settings = discussionConfig,
+  connectionFactory = createConnection,
+  solve = solvePuzzle,
+} = {}) {
+  const local = api.storage.local;
+  const origin = settings.apiOrigin.replace(/\/$/, "");
+  const pendingRequests = new Map();
+  const reactionQueues = new Map();
+  const navigationScopes = new Map();
+  let generation = 0;
+  let accountEpoch = 0;
+  let token = "";
+  let session = { ...ANONYMOUS_SESSION };
+  let connection = null;
+  let connecting = null;
+  let accountQueue = Promise.resolve();
+  let catchupQueue = Promise.resolve();
+  let stateQueue = Promise.resolve();
+  let rejectedToken = "";
+  let accountBlocked = false;
+  let hintedRevision = "0";
+  let hasInboxSnapshot = false;
+  let inbox = { items: [], unreadCount: 0, revision: "0", nextCursor: null };
+  let stopped = false;
+
+  const store = (method, ...args) => callBrowser(api, local, method, ...args);
+  const writeState = (expected, method, ...args) => {
+    const work = stateQueue
+      .catch(() => {})
+      .then(() => {
+        if (expected !== generation) return;
+        return store(method, ...args);
+      });
+    stateQueue = work;
+    return work;
+  };
+  const credentials = settings.testMode
+    ? createVoteClient({
+        apiBaseUrl: origin,
+        fetchImpl,
+        credentialStore: {
+          async load() {
+            return (await store("get", [settings.credentialStorageKey]))?.[settings.credentialStorageKey] ?? null;
+          },
+          async save(value) {
+            await store("set", { [settings.credentialStorageKey]: value });
+          },
+          async clear() {
+            await store("remove", [settings.credentialStorageKey]);
+          },
+        },
+        cryptoImpl: globalThis.crypto,
+      })
+    : voteClient;
+
+  function assertCurrent(expected) {
+    if (stopped || expected !== generation) throw new DiscussionError("session_changed");
+  }
+
+  function assertScope(scope) {
+    if (scope?.cancelled) throw new DiscussionError("navigation_changed", "The video changed");
+  }
+
+  function scopeFor(value, sender) {
+    if (!value) return null;
+    const documentId = sender.documentId || "top-frame";
+    const key = `${sender.tab.id}:${documentId}:${value.id}`;
+    if (!navigationScopes.has(key))
+      navigationScopes.set(key, {
+        tabId: sender.tab.id,
+        documentId,
+        videoId: value.videoId,
+        cancelled: false,
+        controllers: new Set(),
+      });
+    const scope = navigationScopes.get(key);
+    if (scope.videoId !== value.videoId) throw new DiscussionError("invalid_scope");
+    return scope;
+  }
+
+  function cancelScope(scope) {
+    scope.cancelled = true;
+    for (const controller of scope.controllers) controller.abort();
+  }
+
+  async function request(
+    path,
+    { method = "GET", body, auth = token, expected = generation, scope, accountBound = true } = {},
+  ) {
+    const assertRequest = () => assertCurrent(accountBound ? expected : generation);
+    assertRequest();
+    assertScope(scope);
+    const controller = new AbortController();
+    pendingRequests.set(controller, accountBound);
+    scope?.controllers.add(controller);
+    const timeout = setTimeout(() => controller.abort(), 20000);
+    try {
+      const response = await fetchImpl(`${origin}/api/discussion${path}`, {
+        method,
+        credentials: "omit",
+        cache: "no-store",
+        signal: controller.signal,
+        headers: {
+          Accept: "application/json",
+          ...(body == null ? {} : { "Content-Type": "application/json" }),
+          ...(auth ? { Authorization: `Bearer ${auth}` } : {}),
+        },
+        ...(body == null ? {} : { body: JSON.stringify(body) }),
+      });
+      assertRequest();
+      assertScope(scope);
+      const data = response.status === 204 ? null : await response.json().catch(() => null);
+      assertRequest();
+      assertScope(scope);
+      if (!response.ok) {
+        if (
+          response.status === 401 &&
+          data?.code === "authentication_required" &&
+          accountBound &&
+          auth &&
+          auth === token &&
+          path !== "/me"
+        ) {
+          rejectedToken = token;
+          clearSession();
+        }
+        throw new DiscussionError(data?.code || "request_failed", data?.message || "Request failed", response.status);
+      }
+      return data;
+    } catch (error) {
+      assertScope(scope);
+      if (error instanceof DiscussionError) throw error;
+      throw new DiscussionError(
+        controller.signal.aborted ? "request_cancelled" : "network_error",
+        "Discussion is unavailable",
+      );
+    } finally {
+      clearTimeout(timeout);
+      pendingRequests.delete(controller);
+      scope?.controllers.delete(controller);
+    }
+  }
+
+  async function broadcast(type, data, expected = generation) {
+    const message = { message: "ryd_discussion_event", type, data };
+    if (expected !== generation || stopped) return;
+    const tabs = await callBrowser(
+      api,
+      api.tabs,
+      "query",
+      type === "toast" ? { active: true, lastFocusedWindow: true } : {},
+    );
+    if (expected !== generation || stopped) return;
+    const targets = (tabs || []).filter((tab) => isYouTubePage(tab.url));
+    await Promise.allSettled(
+      (type === "toast" ? targets.slice(0, 1) : targets).map((tab) =>
+        callBrowser(api, api.tabs, "sendMessage", tab.id, message),
+      ),
+    );
+    if (type !== "toast" && expected === generation) {
+      await callBrowser(api, api.runtime, "sendMessage", message).catch(() => {});
+    }
+  }
+
+  async function updateBadge(expected = generation) {
+    if (expected !== generation || stopped) return;
+    const action = api.action || api.browserAction;
+    await callBrowser(api, action, "setBadgeText", {
+      text: inbox.unreadCount ? String(Math.min(inbox.unreadCount, 99)) + (inbox.unreadCount > 99 ? "+" : "") : "",
+    }).catch(() => {});
+    if (expected === generation)
+      await callBrowser(api, action, "setBadgeBackgroundColor", { color: "#cc0000" }).catch(() => {});
+  }
+
+  async function publishInbox(expected, changed = [], showToast = false) {
+    assertCurrent(expected);
+    await writeState(expected, "set", {
+      [settings.stateStorageKey]: { profileId: session.profile?.id ?? null, ...inbox },
+    });
+    assertCurrent(expected);
+    await updateBadge(expected);
+    await broadcast("inbox", inbox, expected);
+    if (showToast) {
+      const notification = changed.find((item) => !item.read && ["reply", "likes"].includes(item.type));
+      if (notification) await broadcast("toast", notification, expected);
+    }
+  }
+
+  function catchup(showToast = false, expected = generation) {
+    const work = catchupQueue
+      .catch(() => {})
+      .then(async () => {
+        assertCurrent(expected);
+        if (!session.authenticated || !token) return;
+        const since = inbox.revision;
+        const isChanges = hasInboxSnapshot;
+        const changed = [];
+        let cursor = null;
+        let page;
+        do {
+          const params = new URLSearchParams();
+          if (isChanges) params.set("afterRevision", since);
+          if (cursor) params.set("cursor", cursor);
+          page = await request(`/notifications${params.size ? `?${params}` : ""}`, { expected });
+          changed.push(...(page.items || []));
+          cursor = page.nextCursor;
+        } while (cursor && isChanges);
+        assertCurrent(expected);
+        const previous = new Map(inbox.items.map((item) => [item.id, item]));
+        const novel = changed.filter((item) => previous.get(item.id)?.revision !== item.revision);
+        for (const item of changed) previous.set(item.id, item);
+        inbox = {
+          items: [...previous.values()]
+            .sort((a, b) => String(b.updatedAt).localeCompare(String(a.updatedAt)))
+            .slice(0, 100),
+          nextCursor: isChanges ? inbox.nextCursor : page.nextCursor,
+          unreadCount: page.unreadCount,
+          revision: page.revision,
+        };
+        hasInboxSnapshot = true;
+        await publishInbox(expected, novel, showToast && isChanges);
+      });
+    catchupQueue = work;
+    return work;
+  }
+
+  async function connect(expected = generation) {
+    if (connecting || connection || !session.authenticated || !token || stopped) return connecting;
+    const work = (async () => {
+      assertCurrent(expected);
+      const activeToken = token;
+      const socket = connectionFactory(`${origin}/api/discussion/notifications/hub`, async () => {
+        assertCurrent(expected);
+        const ticket = await request("/notifications/ticket", { method: "POST", auth: activeToken, expected });
+        return ticket.token;
+      });
+      connection = socket;
+      socket.on("NotificationsChanged", (event) => {
+        const revision = event?.revision;
+        if (expected !== generation || typeof revision !== "string" || !/^(0|[1-9][0-9]*)$/.test(revision)) return;
+        if (BigInt(revision) <= BigInt(inbox.revision) || BigInt(revision) <= BigInt(hintedRevision)) return;
+        hintedRevision = revision;
+        catchup(true, expected).catch(() => {
+          if (expected === generation) hintedRevision = inbox.revision;
+        });
+      });
+      socket.onclose(() => {
+        if (connection === socket) connection = null;
+      });
+      socket.onreconnected(() => {
+        if (expected !== generation || connection !== socket || stopped) return;
+        catchup(false, expected).catch(() => {});
+      });
+      try {
+        await socket.start();
+        assertCurrent(expected);
+        await catchup(false, expected).catch(() => {});
+      } catch (error) {
+        if (connection === socket) connection = null;
+        await socket.stop().catch(() => {});
+        throw error;
+      }
+    })();
+    connecting = work;
+    try {
+      await work;
+    } finally {
+      if (connecting === work) connecting = null;
+    }
+  }
+
+  function clearSession(blockAccount = false, preserveQueuedRequests = false) {
+    if (blockAccount) accountBlocked = true;
+    if (!preserveQueuedRequests) accountEpoch++;
+    generation++;
+    for (const [controller, accountBound] of pendingRequests) if (accountBound) controller.abort();
+    const previousConnection = connection;
+    connection = null;
+    connecting = null;
+    previousConnection?.stop().catch(() => {});
+    token = "";
+    hintedRevision = "0";
+    hasInboxSnapshot = false;
+    session = { ...ANONYMOUS_SESSION };
+    inbox = { items: [], unreadCount: 0, revision: "0", nextCursor: null };
+    writeState(generation, "remove", [settings.stateStorageKey]).catch(() => {});
+    updateBadge().catch(() => {});
+    broadcast("session", session).catch(() => {});
+    broadcast("inbox", inbox).catch(() => {});
+  }
+
+  function refreshSession() {
+    const work = accountQueue
+      .catch(() => {})
+      .then(async () => {
+        const beforeRead = generation;
+        if (stopped || accountBlocked) return session;
+        const consent = await hasConsent();
+        assertCurrent(beforeRead);
+        let nextToken = "";
+        if (consent) {
+          if (settings.testMode) {
+            const data = await store("get", [settings.authStorageKey]);
+            nextToken = data?.[settings.authStorageKey]?.sessionToken || "";
+          } else {
+            const data = await callBrowser(api, api.storage.sync, "get", [
+              "patreonAuthenticated",
+              "patreonSessionToken",
+            ]);
+            nextToken = data?.patreonAuthenticated ? data.patreonSessionToken || "" : "";
+          }
+        }
+        assertCurrent(beforeRead);
+        if (
+          (nextToken && nextToken === rejectedToken) ||
+          (nextToken === token && (!nextToken || session.authenticated))
+        )
+          return session;
+        clearSession(false, true);
+        const expected = generation;
+        token = nextToken;
+        if (!token) return session;
+        try {
+          session = safeSession(await request("/me", { expected }));
+        } catch (error) {
+          assertCurrent(expected);
+          if (error.status !== 401) throw error;
+          rejectedToken = token;
+          token = "";
+          session = { ...ANONYMOUS_SESSION };
+          return session;
+        }
+        assertCurrent(expected);
+        await broadcast("session", session, expected);
+        await catchup(false, expected).catch(() => {});
+        connect(expected).catch(() => {});
+        return session;
+      });
+    accountQueue = work;
+    return work;
+  }
+
+  async function withReactions(result, expected, single = false, scope) {
+    assertScope(scope);
+    const items = single ? [result] : result.items || [];
+    if (!items.length) return result;
+    try {
+      const registered = await credentials.getRegisteredUser();
+      assertCurrent(expected);
+      assertScope(scope);
+      if (!registered) {
+        for (const item of items) item.myReaction = 0;
+        return result;
+      }
+      const { userId } = registered;
+      const values = await request("/reactions/state", {
+        method: "POST",
+        body: { userId, commentIds: items.map((item) => item.id) },
+        expected,
+        scope,
+      });
+      const ownValues = new Map((values.items || []).map((item) => [item.commentId, item.value]));
+      for (const item of items) item.myReaction = ownValues.get(item.id) ?? 0;
+    } catch (error) {
+      assertCurrent(expected);
+      assertScope(scope);
+      // Public reading remains available when stored vote credentials are unavailable.
+    }
+    return result;
+  }
+
+  function react(payload, expected, scope) {
+    const previous = reactionQueues.get(payload.id) || Promise.resolve();
+    const work = previous
+      .catch(() => {})
+      .then(async () => {
+        assertCurrent(expected);
+        assertScope(scope);
+        const { userId } = await credentials.ensureRegistered();
+        assertCurrent(expected);
+        assertScope(scope);
+        for (let attempt = 0; attempt < 3; attempt++) {
+          const puzzle = await request(`/comments/${payload.id}/reaction/challenge`, {
+            method: "POST",
+            body: { userId, value: payload.value },
+            expected,
+            scope,
+          });
+          const solved = await solve(puzzle);
+          assertCurrent(expected);
+          assertScope(scope);
+          if (!solved) continue;
+          return request(`/comments/${payload.id}/reaction/confirm`, {
+            method: "POST",
+            body: { userId, challengeId: puzzle.challengeId, solution: solved.solution },
+            expected,
+            scope,
+          });
+        }
+        throw new DiscussionError("puzzle_failed", "Please try the reaction again");
+      });
+    reactionQueues.set(payload.id, work);
+    work
+      .finally(() => {
+        if (reactionQueues.get(payload.id) === work) reactionQueues.delete(payload.id);
+      })
+      .catch(() => {});
+    return work;
+  }
+
+  async function execute(operation, payload, scope) {
+    assertScope(scope);
+    if (operation === "capabilities") return request("/capabilities", { auth: "", accountBound: false });
+    const queuedEpoch = accountEpoch;
+    await refreshSession();
+    if (queuedEpoch !== accountEpoch) throw new DiscussionError("session_changed");
+    assertScope(scope);
+    const expected = generation;
+    const { id, cursor } = payload;
+    const query = cursor ? `?cursor=${encodeURIComponent(cursor)}` : "";
+    const send = (path, options = {}) => request(path, { ...options, scope });
+    switch (operation) {
+      case "session":
+        return session;
+      case "profile": {
+        const data = safeSession(
+          await send("/me/profile", { method: "PUT", body: { nickname: payload.nickname }, expected }),
+        );
+        session = data;
+        await broadcast("session", session, expected);
+        return data;
+      }
+      case "comments":
+        return withReactions(
+          await send(
+            `/videos/${payload.videoId}/comments?sort=${payload.sort || "top"}${cursor ? `&cursor=${encodeURIComponent(cursor)}` : ""}`,
+            { expected },
+          ),
+          expected,
+          false,
+          scope,
+        );
+      case "replies":
+        return withReactions(
+          await send(`/comments/${payload.rootId}/replies${query}`, { expected }),
+          expected,
+          false,
+          scope,
+        );
+      case "comment":
+        return withReactions(await send(`/comments/${id}`, { expected }), expected, true, scope);
+      case "createComment": {
+        const { videoId, ...body } = payload;
+        return send(`/videos/${videoId}/comments`, { method: "POST", body, expected });
+      }
+      case "editComment":
+        return send(`/comments/${id}`, { method: "PATCH", body: { text: payload.text }, expected });
+      case "deleteComment":
+        return send(`/comments/${id}`, { method: "DELETE", expected });
+      case "react":
+        return react(payload, expected, scope);
+      case "report":
+        return send(`/comments/${id}/reports`, { method: "POST", body: { reason: payload.reason }, expected });
+      case "reports":
+        return request(
+          `/moderation/reports?status=${payload.status || "open"}${cursor ? `&cursor=${encodeURIComponent(cursor)}` : ""}`,
+          { expected },
+        );
+      case "dismissReport":
+        return request(`/moderation/reports/${id}/dismiss`, {
+          method: "POST",
+          body: { reason: payload.reason },
+          expected,
+        });
+      case "moderateComment":
+        return request(`/moderation/comments/${id}`, {
+          method: "POST",
+          body: { hidden: payload.hidden, reason: payload.reason },
+          expected,
+        });
+      case "suspendProfile":
+        return request(`/moderation/profiles/${id}/suspension`, {
+          method: "POST",
+          body: { suspended: payload.suspended, reason: payload.reason },
+          expected,
+        });
+      case "notifications":
+        return request(`/notifications${query}`, { expected });
+      case "readNotifications": {
+        const data = await request("/notifications/read", { method: "POST", body: payload, expected });
+        await catchup(false, expected);
+        return data;
+      }
+      default:
+        throw new DiscussionError("invalid_request");
+    }
+  }
+
+  async function handleMessage(requestMessage, sender) {
+    try {
+      const { operation, payload, scope: scopeValue } = validateRequest(api, requestMessage, sender);
+      const scope = scopeFor(scopeValue, sender);
+      if (operation === "cancelScope") {
+        cancelScope(scope);
+        return { ok: true, data: { cancelled: true } };
+      }
+      const data = await execute(operation, payload, scope);
+      assertScope(scope);
+      if (
+        scope &&
+        ((data?.videoId && data.videoId !== scope.videoId) ||
+          data?.items?.some((item) => item.videoId && item.videoId !== scope.videoId))
+      )
+        throw new DiscussionError("navigation_changed");
+      return { ok: true, data };
+    } catch (error) {
+      return {
+        ok: false,
+        error: {
+          code: error.code || "request_failed",
+          message: error.message || "Request failed",
+          status: error.status || 0,
+        },
+      };
+    }
+  }
+
+  function onStorageChanged(changes, area) {
+    const changed = settings.testMode
+      ? area === "local" && changes[settings.authStorageKey]
+      : area === "sync" && (changes.patreonAuthenticated || changes.patreonSessionToken || changes.patreonUser);
+    if (changed) {
+      rejectedToken = "";
+      clearSession();
+      refreshSession().catch(() => {});
+    }
+  }
+
+  function initialize() {
+    api.tabs?.onRemoved?.addListener((tabId) => {
+      for (const [key, scope] of navigationScopes)
+        if (scope.tabId === tabId) {
+          cancelScope(scope);
+          navigationScopes.delete(key);
+        }
+    });
+    api.alarms?.onAlarm?.addListener((alarm) => {
+      if (alarm.name !== RECONNECT_ALARM || stopped) return;
+      refreshSession()
+        .then(() => Promise.allSettled([catchup(false), connect()]))
+        .catch(() => {});
+    });
+    // Alarm recovery also covers service-worker termination and offline browser startup.
+    api.alarms?.create(RECONNECT_ALARM, { periodInMinutes: 1 });
+    refreshSession().catch(() => {});
+  }
+
+  return {
+    handleMessage,
+    refreshSession,
+    clearSession,
+    resumeSession() {
+      accountBlocked = false;
+      return refreshSession();
+    },
+    onStorageChanged,
+    initialize,
+    stop() {
+      clearSession();
+      stopped = true;
+      for (const controller of pendingRequests.keys()) controller.abort();
+      api.alarms?.clear(RECONNECT_ALARM);
+    },
+  };
+}
+
+export { ANONYMOUS_SESSION, createConnection, validateRequest };
diff --git a/Extensions/combined/src/discussion-background.spec.js b/Extensions/combined/src/discussion-background.spec.js
new file mode 100644
index 0000000..9bb1999
--- /dev/null
+++ b/Extensions/combined/src/discussion-background.spec.js
@@ -0,0 +1,574 @@
+import { createDiscussionBackground, ANONYMOUS_SESSION } from "./discussion-background";
+
+const ID = "11111111-1111-4111-8111-111111111111";
+const PROFILE_ID = "22222222-2222-4222-8222-222222222222";
+const NOTIFICATION_ID = "33333333-3333-4333-8333-333333333333";
+const VIDEO_ID = "video123456";
+const ORIGIN = "https://returnyoutubedislikeapi.com";
+const SCOPE = { id: "44444444-4444-4444-8444-444444444444", videoId: VIDEO_ID };
+const VIDEO_OPERATIONS = new Set([
+  "comments",
+  "replies",
+  "comment",
+  "createComment",
+  "editComment",
+  "deleteComment",
+  "react",
+  "report",
+  "cancelScope",
+]);
+const sender = {
+  id: "extension-id",
+  url: `https://www.youtube.com/watch?v=${VIDEO_ID}`,
+  tab: { id: 1, url: `https://www.youtube.com/watch?v=${VIDEO_ID}` },
+  frameId: 0,
+};
+const flush = () => new Promise((resolve) => setTimeout(resolve, 0));
+const deferred = () => {
+  let resolve;
+  const promise = new Promise((done) => {
+    resolve = done;
+  });
+  return { promise, resolve };
+};
+
+function storageArea(data = {}) {
+  return {
+    data,
+    get: jest.fn((keys, callback) => callback(Object.fromEntries(keys.map((key) => [key, data[key]])))),
+    set: jest.fn((values, callback) => {
+      Object.assign(data, values);
+      callback?.();
+    }),
+    remove: jest.fn((keys, callback) => {
+      keys.forEach((key) => delete data[key]);
+      callback?.();
+    }),
+  };
+}
+
+function harness({ authenticated = false, consent = true, fetchOverride, testMode = false, solveOverride } = {}) {
+  const sync = storageArea(authenticated ? { patreonAuthenticated: true, patreonSessionToken: "account-token" } : {});
+  const local = storageArea();
+  let alarmListener;
+  const api = {
+    runtime: {
+      id: "extension-id",
+      getURL: (path) => `chrome-extension://extension-id/${path}`,
+      sendMessage: jest.fn((message, callback) => callback?.()),
+    },
+    storage: { sync, local },
+    action: {
+      setBadgeText: jest.fn((value, callback) => callback?.()),
+      setBadgeBackgroundColor: jest.fn((value, callback) => callback?.()),
+    },
+    tabs: {
+      query: jest.fn((query, callback) =>
+        callback([
+          { id: 1, url: sender.url },
+          { id: 2, url: sender.url },
+          { id: 3, url: "https://example.com/" },
+        ]),
+      ),
+      sendMessage: jest.fn((id, message, callback) => callback?.()),
+    },
+    alarms: {
+      create: jest.fn(),
+      clear: jest.fn(),
+      onAlarm: {
+        addListener: (listener) => {
+          alarmListener = listener;
+        },
+      },
+    },
+  };
+  const notification = {
+    id: NOTIFICATION_ID,
+    type: "likes",
+    commentId: ID,
+    rootId: ID,
+    videoId: VIDEO_ID,
+    actorNickname: null,
+    likeCount: 1,
+    read: false,
+    createdAt: "2026-09-06T10:00:00Z",
+    updatedAt: "2026-09-06T10:00:00Z",
+    revision: "1",
+  };
+  let inbox = {
+    items: authenticated ? [notification] : [],
+    unreadCount: authenticated ? 1 : 0,
+    revision: "1",
+    nextCursor: null,
+  };
+  const calls = [];
+  const fetchImpl = jest.fn(async (url, options) => {
+    const path = url.replace(`${ORIGIN}/api/discussion`, "");
+    const body = options.body ? JSON.parse(options.body) : null;
+    calls.push({ path, body, options, url });
+    if (fetchOverride) {
+      const override = await fetchOverride(path, options, body);
+      if (override) return override;
+    }
+    let data;
+    if (path === "/me" || path === "/me/profile")
+      data = {
+        authenticated: true,
+        canPost: true,
+        isModerator: false,
+        membershipTier: "commenter",
+        profile: { id: PROFILE_ID, nickname: "Tester", suspended: false, providerId: "private" },
+        token: "private",
+        userId: "private",
+      };
+    else if (path.startsWith("/notifications/ticket"))
+      data = { token: "hub-ticket", expiresAt: "2026-09-06T10:01:00Z" };
+    else if (path.startsWith("/notifications")) data = inbox;
+    else if (path.endsWith("/reaction/challenge"))
+      data = { challengeId: ID, challenge: "AAAAAAAAAAAAAAAAAAAAAA==", difficulty: 1 };
+    else if (path.endsWith("/reaction/confirm")) data = { commentId: ID, likes: 1, dislikes: 0, myReaction: 1 };
+    else if (path === "/reactions/state") data = { items: [{ commentId: ID, value: -1 }] };
+    else if (path.includes("/comments"))
+      data = {
+        items: [{ id: ID, videoId: VIDEO_ID, author: { id: PROFILE_ID, nickname: "Tester" }, text: "Hello" }],
+        nextCursor: null,
+      };
+    else data = { enabled: true };
+    return { ok: true, status: 200, json: async () => structuredClone(data) };
+  });
+  const sockets = [];
+  const connectionFactory = jest.fn((url, tokenFactory) => {
+    const handlers = {};
+    const socket = {
+      url,
+      tokenFactory,
+      handlers,
+      on: (name, handler) => {
+        handlers[name] = handler;
+      },
+      onclose: (handler) => {
+        handlers.close = handler;
+      },
+      onreconnected: (handler) => {
+        handlers.reconnected = handler;
+      },
+      start: jest.fn(async () => {
+        await tokenFactory();
+      }),
+      stop: jest.fn(async () => {}),
+    };
+    sockets.push(socket);
+    return socket;
+  });
+  const voteClient = {
+    ensureRegistered: jest.fn(async () => ({ userId: "existing-voter-secret" })),
+    getRegisteredUser: jest.fn(async () => ({ userId: "existing-voter-secret" })),
+  };
+  const client = createDiscussionBackground({
+    api,
+    voteClient,
+    fetchImpl,
+    hasConsent: async () => consent,
+    connectionFactory,
+    solve: solveOverride || jest.fn(async () => ({ solution: "AAAAAA==" })),
+    settings: {
+      apiOrigin: ORIGIN,
+      testMode,
+      authStorageKey: "testAuth",
+      credentialStorageKey: "testCredentials",
+      stateStorageKey: "discussionState",
+    },
+  });
+  return {
+    api,
+    client,
+    calls,
+    sockets,
+    fetchImpl,
+    voteClient,
+    sync,
+    local,
+    notification,
+    setInbox: (value) => {
+      inbox = value;
+    },
+    alarm: () => alarmListener({ name: "ryd-discussion-reconnect" }),
+    send: (operation, payload = {}, source = sender, scope = SCOPE) =>
+      client.handleMessage(
+        {
+          message: "ryd_discussion",
+          operation,
+          payload,
+          ...(VIDEO_OPERATIONS.has(operation) && scope ? { scope } : {}),
+        },
+        source,
+      ),
+  };
+}
+
+describe("discussion worker boundary", () => {
+  test("public comments do not create a voter identity before the first reaction", async () => {
+    const h = harness();
+    h.voteClient.getRegisteredUser.mockResolvedValue(null);
+    const response = await h.send("comments", { videoId: VIDEO_ID, sort: "new" });
+    expect(response.ok).toBe(true);
+    expect(response.data.items[0].myReaction).toBe(0);
+    expect(h.voteClient.ensureRegistered).not.toHaveBeenCalled();
+    expect(h.calls.some((call) => call.path === "/reactions/state")).toBe(false);
+  });
+  test.each([
+    ["comments", { videoId: VIDEO_ID, userId: "forged" }, sender],
+    ["session", { sessionToken: "forged" }, sender],
+    ["react", { id: ID, value: 1, recipient: "forged" }, sender],
+    ["session", {}, { ...sender, id: "different-extension" }],
+    ["session", {}, { ...sender, frameId: 1 }],
+    ["session", {}, { ...sender, url: "https://www.youtube.com.evil.test/watch?v=video123456" }],
+    ["fetch", { url: "https://example.com" }, sender],
+    ["react", { id: ID, value: 2 }, sender],
+    ["createComment", { videoId: VIDEO_ID, text: "Hi" }, sender],
+  ])("rejects invalid %s requests before sending network traffic", async (operation, payload, source) => {
+    const h = harness();
+    expect((await h.send(operation, payload, source)).ok).toBe(false);
+    expect(h.fetchImpl).not.toHaveBeenCalled();
+  });
+
+  test("public reads enrich viewer reactions without exposing the voter credential", async () => {
+    const h = harness();
+    const response = await h.send("comments", { videoId: VIDEO_ID, sort: "new" });
+    expect(response.ok).toBe(true);
+    expect(response.data.items[0].myReaction).toBe(-1);
+    expect(JSON.stringify(response)).not.toContain("existing-voter-secret");
+    expect(h.calls.find((call) => call.path === "/reactions/state").body).toEqual({
+      userId: "existing-voter-secret",
+      commentIds: [ID],
+    });
+    expect(h.calls.every((call) => !call.options.headers.Authorization)).toBe(true);
+    expect(h.sockets).toHaveLength(0);
+  });
+
+  test("preserves the same anonymous reaction identity across sign-in and sign-out", async () => {
+    const h = harness();
+    await h.send("react", { id: ID, value: 1 });
+    Object.assign(h.sync.data, { patreonAuthenticated: true, patreonSessionToken: "account-token" });
+    await h.send("react", { id: ID, value: -1 });
+    delete h.sync.data.patreonSessionToken;
+    await h.send("react", { id: ID, value: 0 });
+    expect(h.calls.filter((call) => call.path.endsWith("/reaction/challenge")).map((call) => call.body)).toEqual([
+      { userId: "existing-voter-secret", value: 1 },
+      { userId: "existing-voter-secret", value: -1 },
+      { userId: "existing-voter-secret", value: 0 },
+    ]);
+    expect(h.sync.set).not.toHaveBeenCalled();
+    expect(h.sync.remove).not.toHaveBeenCalled();
+    expect((await h.send("session")).data).toEqual(ANONYMOUS_SESSION);
+    h.client.stop();
+  });
+
+  test("returns a safe server session to the popup and uses only hub tickets on sockets", async () => {
+    const h = harness({ authenticated: true });
+    const response = await h.send(
+      "session",
+      {},
+      { id: "extension-id", url: "chrome-extension://extension-id/popup.html" },
+    );
+    await flush();
+    expect(response.data.profile).toEqual({ id: PROFILE_ID, nickname: "Tester", suspended: false });
+    expect(JSON.stringify(response)).not.toMatch(/private|account-token|existing-voter-secret/);
+    expect(h.sockets).toHaveLength(1);
+    expect(await h.sockets[0].tokenFactory()).toBe("hub-ticket");
+    expect(h.sockets[0].url).not.toContain("token");
+    h.client.stop();
+  });
+
+  test("does not read or transmit stored account credentials after consent removal", async () => {
+    const h = harness({ authenticated: true, consent: false });
+    expect((await h.send("session")).data).toEqual(ANONYMOUS_SESSION);
+    expect(h.sync.get).not.toHaveBeenCalled();
+    expect(h.fetchImpl).not.toHaveBeenCalled();
+  });
+
+  test("test accounts never fall back to real Patreon storage", async () => {
+    const h = harness({ authenticated: true, testMode: true });
+    expect((await h.send("session")).data).toEqual(ANONYMOUS_SESSION);
+    expect(h.sync.get).not.toHaveBeenCalled();
+    expect(h.fetchImpl).not.toHaveBeenCalled();
+  });
+
+  test("discards an account response arriving after logout", async () => {
+    const pending = deferred();
+    const h = harness({ authenticated: true, fetchOverride: (path) => (path === "/me" ? pending.promise : undefined) });
+    const response = h.send("session");
+    await flush();
+    h.client.clearSession();
+    pending.resolve({
+      ok: true,
+      status: 200,
+      json: async () => ({ authenticated: true, canPost: true, profile: { id: PROFILE_ID, nickname: "Old account" } }),
+    });
+    expect((await response).ok).toBe(false);
+    expect(
+      h.api.tabs.sendMessage.mock.calls.some(([, event]) => event.type === "session" && event.data.authenticated),
+    ).toBe(false);
+    expect(h.sockets).toHaveLength(0);
+  });
+
+  test("the public capability probe survives account initialization and logout", async () => {
+    const pending = deferred();
+    let signal;
+    const h = harness({
+      fetchOverride: (path, options) => {
+        if (path !== "/capabilities") return;
+        signal = options.signal;
+        return pending.promise;
+      },
+    });
+    const response = h.send("capabilities");
+    await flush();
+    h.client.clearSession();
+    expect(signal.aborted).toBe(false);
+    pending.resolve({ ok: true, status: 200, json: async () => ({ enabled: true }) });
+    expect(await response).toEqual({ ok: true, data: { enabled: true } });
+    expect(h.calls[0].options.headers.Authorization).toBeUndefined();
+    h.client.stop();
+  });
+
+  test("does not restore an old account while logout storage cleanup is pending", async () => {
+    const h = harness({ authenticated: true });
+    await h.send("session");
+    h.client.clearSession(true);
+    expect((await h.send("session")).data).toEqual(ANONYMOUS_SESSION);
+    delete h.sync.data.patreonSessionToken;
+    await h.client.resumeSession();
+    expect((await h.send("session")).data).toEqual(ANONYMOUS_SESSION);
+    h.client.stop();
+  });
+
+  test("a request queued across an account change cannot execute under the replacement account", async () => {
+    const held = deferred();
+    const h = harness({ authenticated: true, fetchOverride: (path) => (path === "/me" ? held.promise : undefined) });
+    const reading = h.send("session");
+    await flush();
+    const queued = h.send("createComment", { videoId: VIDEO_ID, text: "Old account draft", requestId: ID });
+    h.client.clearSession(true);
+    held.resolve({ ok: true, status: 200, json: async () => ({ authenticated: true }) });
+    expect((await reading).ok).toBe(false);
+    expect((await queued).error.code).toBe("session_changed");
+    expect(h.calls.some((call) => call.path.includes("/videos/"))).toBe(false);
+    h.client.stop();
+  });
+
+  test("moderation reports accept only open or resolved status and encode their cursor", async () => {
+    const h = harness();
+    expect((await h.send("reports", { status: "resolved", cursor: "opaque&value" })).ok).toBe(true);
+    expect(h.calls.at(-1).path).toBe("/moderation/reports?status=resolved&cursor=opaque%26value");
+    expect((await h.send("reports", { status: "hidden" })).error.code).toBe("invalid_request");
+  });
+
+  test("serializes reactions so a slow confirmation cannot overwrite a newer choice", async () => {
+    const pending = deferred();
+    let confirms = 0;
+    const h = harness({
+      fetchOverride: (path) => (path.endsWith("/reaction/confirm") && confirms++ === 0 ? pending.promise : undefined),
+    });
+    const first = h.send("react", { id: ID, value: 1 });
+    const second = h.send("react", { id: ID, value: -1 });
+    await flush();
+    expect(h.calls.filter((call) => call.path.endsWith("/reaction/challenge"))).toHaveLength(1);
+    pending.resolve({
+      ok: true,
+      status: 200,
+      json: async () => ({ commentId: ID, likes: 1, dislikes: 0, myReaction: 1 }),
+    });
+    await Promise.all([first, second]);
+    expect(h.calls.filter((call) => call.path.endsWith("/reaction/challenge")).map((call) => call.body.value)).toEqual([
+      1, -1,
+    ]);
+  });
+
+  test("updates grouped notification revisions and emits one active-tab toast without replaying history", async () => {
+    const h = harness({ authenticated: true });
+    await h.send("session");
+    await flush();
+    expect(h.api.tabs.sendMessage.mock.calls.filter(([, event]) => event.type === "toast")).toHaveLength(0);
+    expect(h.api.action.setBadgeText).toHaveBeenLastCalledWith({ text: "1" }, expect.any(Function));
+    const updated = { ...h.notification, revision: "2", likeCount: 2, updatedAt: "2026-09-06T10:05:00Z" };
+    h.setInbox({ items: [updated], unreadCount: 1, revision: "2", nextCursor: null });
+    h.sockets[0].handlers.NotificationsChanged({ revision: "2" });
+    await flush();
+    await flush();
+    h.sockets[0].handlers.NotificationsChanged({ revision: "2" });
+    await flush();
+    const toasts = h.api.tabs.sendMessage.mock.calls.filter(([, event]) => event.type === "toast");
+    expect(toasts).toHaveLength(1);
+    expect(toasts[0][0]).toBe(1);
+    expect(toasts[0][1].data.likeCount).toBe(2);
+    expect(h.calls.some((call) => call.path === "/notifications?afterRevision=1")).toBe(true);
+    h.client.stop();
+  });
+
+  test("alarm reconnects a closed socket and silently catches up notifications", async () => {
+    const h = harness({ authenticated: true });
+    h.client.initialize();
+    await flush();
+    await flush();
+    h.sockets[0].handlers.close();
+    h.alarm();
+    await flush();
+    await flush();
+    expect(h.sockets).toHaveLength(2);
+    expect(h.api.tabs.sendMessage.mock.calls.filter(([, event]) => event.type === "toast")).toHaveLength(0);
+    h.client.stop();
+  });
+
+  test("a reconnect callback from a cleared account cannot request its old inbox", async () => {
+    const h = harness({ authenticated: true });
+    await h.send("session");
+    await flush();
+    const oldSocket = h.sockets[0];
+    h.client.clearSession(true);
+    await flush();
+    const count = h.calls.length;
+    oldSocket.handlers.reconnected();
+    await flush();
+    expect(h.calls).toHaveLength(count);
+    h.client.stop();
+  });
+
+  test("an expired cached account clears its inbox, badge and socket without changing the voter identity", async () => {
+    const h = harness({
+      authenticated: true,
+      fetchOverride: (path) =>
+        path.includes("cursor=expired")
+          ? { ok: false, status: 401, json: async () => ({ code: "authentication_required" }) }
+          : undefined,
+    });
+    await h.send("session");
+    await flush();
+    expect((await h.send("notifications", { cursor: "expired" })).error.status).toBe(401);
+    await flush();
+    expect((await h.send("session")).data).toEqual(ANONYMOUS_SESSION);
+    expect(h.sockets[0].stop).toHaveBeenCalled();
+    expect(h.api.action.setBadgeText).toHaveBeenLastCalledWith({ text: "" }, expect.any(Function));
+    expect(
+      h.api.tabs.sendMessage.mock.calls.some(([, event]) => event.type === "inbox" && event.data.items.length === 0),
+    ).toBe(true);
+    expect((await h.send("react", { id: ID, value: -1 })).ok).toBe(true);
+    const challenge = h.calls.findLast((call) => call.path.endsWith("/reaction/challenge"));
+    expect(challenge.body.userId).toBe("existing-voter-secret");
+    expect(challenge.options.headers.Authorization).toBeUndefined();
+    h.client.stop();
+  });
+
+  test("live inbox preserves history pagination without advancing its baseline from a manual history page", async () => {
+    let revision = "25";
+    const h = harness({
+      authenticated: true,
+      fetchOverride: (path) =>
+        path.includes("cursor=manual-history")
+          ? { ok: true, status: 200, json: async () => ({ items: [], revision: "999", nextCursor: null }) }
+          : path.includes("afterRevision=")
+            ? {
+                ok: true,
+                status: 200,
+                json: async () => ({
+                  items: revision === "26" ? [{ ...h.notification, revision }] : [],
+                  unreadCount: 25,
+                  revision,
+                  nextCursor: null,
+                }),
+              }
+            : undefined,
+    });
+    h.setInbox({ items: [h.notification], unreadCount: 25, revision: "25", nextCursor: "older-history" });
+    await h.send("session");
+    await flush();
+    expect((await h.send("notifications", { cursor: "manual-history" })).data.revision).toBe("999");
+    revision = "26";
+    h.sockets[0].handlers.NotificationsChanged({ revision: "26" });
+    await flush();
+    await flush();
+    const event = h.api.tabs.sendMessage.mock.calls.findLast(([, event]) => event.type === "inbox")[1];
+    expect(event.data.nextCursor).toBe("older-history");
+    expect(h.calls.findLast((call) => call.path.includes("afterRevision=")).path).toBe(
+      "/notifications?afterRevision=25",
+    );
+    expect(event.data.revision).toBe("26");
+    h.client.stop();
+  });
+
+  test("a voter registration rejection does not clear a valid logged-in account or its inbox", async () => {
+    const h = harness({
+      authenticated: true,
+      fetchOverride: (path) =>
+        path.endsWith("/reaction/challenge")
+          ? { ok: false, status: 401, json: async () => ({ code: "voter_registration_required" }) }
+          : undefined,
+    });
+    await h.send("session");
+    await flush();
+    expect((await h.send("react", { id: ID, value: 1 })).error.code).toBe("voter_registration_required");
+    expect((await h.send("session")).data.authenticated).toBe(true);
+    expect(h.sockets[0].stop).not.toHaveBeenCalled();
+    expect(h.api.action.setBadgeText).toHaveBeenLastCalledWith({ text: "1" }, expect.any(Function));
+    h.client.stop();
+  });
+
+  test("navigation aborts only the selected document scope and keeps another document and inbox request alive", async () => {
+    const pending = [];
+    let hold = false;
+    const h = harness({
+      authenticated: true,
+      fetchOverride: (path, options) => {
+        if (!hold || (!path.startsWith("/videos/") && !path.includes("cursor=pending"))) return;
+        return new Promise((resolve, reject) => {
+          pending.push({ path, signal: options.signal, resolve });
+          options.signal.addEventListener("abort", () => reject(new Error("aborted")), { once: true });
+        });
+      },
+    });
+    await h.send("session");
+    await flush();
+    hold = true;
+    const firstSource = { ...sender, documentId: "document-one" };
+    const secondSource = { ...sender, documentId: "document-two" };
+    const first = h.send("comments", { videoId: VIDEO_ID }, firstSource);
+    const second = h.send("comments", { videoId: VIDEO_ID }, secondSource);
+    const inbox = h.send("notifications", { cursor: "pending" });
+    await flush();
+    expect(pending).toHaveLength(3);
+    expect((await h.send("cancelScope", {}, firstSource)).ok).toBe(true);
+    expect(pending[0].signal.aborted).toBe(true);
+    expect(pending[1].signal.aborted).toBe(false);
+    expect(pending[2].signal.aborted).toBe(false);
+    for (const request of pending.slice(1))
+      request.resolve({ ok: true, status: 200, json: async () => ({ items: [], nextCursor: null }) });
+    expect((await first).error.code).toBe("navigation_changed");
+    expect((await second).ok).toBe(true);
+    expect((await inbox).ok).toBe(true);
+    h.client.stop();
+  });
+
+  test("cancelled scopes cannot confirm a solved puzzle or start a queued reaction", async () => {
+    const solved = deferred();
+    const h = harness({ solveOverride: () => solved.promise });
+    const first = h.send("react", { id: ID, value: 1 });
+    const queued = h.send("react", { id: ID, value: -1 });
+    await flush();
+    await h.send("cancelScope");
+    solved.resolve({ solution: "AAAAAA==" });
+    expect((await first).error.code).toBe("navigation_changed");
+    expect((await queued).error.code).toBe("navigation_changed");
+    expect(h.calls.filter((call) => call.path.endsWith("/reaction/challenge"))).toHaveLength(1);
+    expect(h.calls.filter((call) => call.path.endsWith("/reaction/confirm"))).toHaveLength(0);
+    expect((await h.send("comments", { videoId: VIDEO_ID })).error.code).toBe("navigation_changed");
+  });
+
+  test("video operations require a scope bound to the current tab video", async () => {
+    const h = harness();
+    expect((await h.send("comments", { videoId: VIDEO_ID }, sender, null)).error.code).toBe("scope_required");
+    expect(
+      (await h.send("comments", { videoId: VIDEO_ID }, sender, { ...SCOPE, videoId: "other123456" })).error.code,
+    ).toBe("navigation_changed");
+    expect(h.fetchImpl).not.toHaveBeenCalled();
+  });
+});
diff --git a/Extensions/combined/src/discussion-config.js b/Extensions/combined/src/discussion-config.js
new file mode 100644
index 0000000..745fcba
--- /dev/null
+++ b/Extensions/combined/src/discussion-config.js
@@ -0,0 +1,11 @@
+import { getApiUrl } from "./config";
+
+const testOrigin = typeof __RYD_DISCUSSION_TEST_ORIGIN__ === "string" ? __RYD_DISCUSSION_TEST_ORIGIN__ : "";
+
+export const discussionConfig = Object.freeze({
+  apiOrigin: testOrigin || getApiUrl(),
+  testMode: Boolean(testOrigin),
+  authStorageKey: testOrigin ? "rydDiscussionTestAuth" : null,
+  credentialStorageKey: "rydDiscussionTestCredentials",
+  stateStorageKey: testOrigin ? "rydDiscussionTestState" : "rydDiscussionState",
+});
diff --git a/Extensions/combined/src/discussion-navigation-fetch.spec.js b/Extensions/combined/src/discussion-navigation-fetch.spec.js
new file mode 100644
index 0000000..628e084
--- /dev/null
+++ b/Extensions/combined/src/discussion-navigation-fetch.spec.js
@@ -0,0 +1,94 @@
+import { createServer } from "node:http";
+import { createDiscussionBackground } from "./discussion-background";
+
+test("navigation cancels a real HTTP fetch while another tab and the inbox finish normally", async () => {
+  const videoId = "abcdefghijk";
+  const otherVideoId = "zyxwvutsrqp";
+  const held = [];
+  let allRequested;
+  let outgoingClosed;
+  const requested = new Promise((resolve) => {
+    allRequested = resolve;
+  });
+  const closed = new Promise((resolve) => {
+    outgoingClosed = resolve;
+  });
+  const server = createServer((request, response) => {
+    held.push({ url: request.url, response });
+    if (request.url.includes(videoId)) response.once("close", outgoingClosed);
+    if (held.length === 3) allRequested();
+  });
+  await new Promise((resolve) => server.listen(0, "127.0.0.1", resolve));
+  const area = {
+    get: (keys, callback) => callback({}),
+    set: (values, callback) => callback?.(),
+    remove: (keys, callback) => callback?.(),
+  };
+  const api = {
+    runtime: { id: "extension-id", getURL: (path) => `chrome-extension://extension-id/${path}` },
+    storage: { sync: area, local: area },
+  };
+  const signals = new Map();
+  const client = createDiscussionBackground({
+    api,
+    voteClient: { ensureRegistered: async () => ({ userId: "unused" }) },
+    settings: { apiOrigin: `http://127.0.0.1:${server.address().port}`, testMode: false, stateStorageKey: "state" },
+    fetchImpl: (url, options) => {
+      signals.set(new URL(url).pathname, options.signal);
+      return fetch(url, options);
+    },
+  });
+  const sender = (id, video) => ({
+    id: "extension-id",
+    frameId: 0,
+    documentId: `document-${id}`,
+    url: `https://www.youtube.com/watch?v=${video}`,
+    tab: { id, url: `https://www.youtube.com/watch?v=${video}` },
+  });
+  const scope = { id: "44444444-4444-4444-8444-444444444444", videoId };
+  const send = (operation, payload, source, value) =>
+    client.handleMessage(
+      {
+        message: "ryd_discussion",
+        operation,
+        payload,
+        ...(value ? { scope: value } : {}),
+      },
+      source,
+    );
+  try {
+    const outgoing = send("comments", { videoId }, sender(1, videoId), scope);
+    const other = send("comments", { videoId: otherVideoId }, sender(2, otherVideoId), {
+      ...scope,
+      videoId: otherVideoId,
+    });
+    const inbox = send("notifications", { cursor: "pending" }, sender(1, videoId));
+    await requested;
+    const cancellation = await send(
+      "cancelScope",
+      {},
+      {
+        ...sender(1, videoId),
+        tab: { id: 1, url: "https://www.youtube.com/" },
+      },
+      scope,
+    );
+    expect(cancellation.ok).toBe(true);
+    expect((await outgoing).error.code).toBe("navigation_changed");
+    await closed;
+    expect(signals.get(`/api/discussion/videos/${videoId}/comments`).aborted).toBe(true);
+    expect(signals.get(`/api/discussion/videos/${otherVideoId}/comments`).aborted).toBe(false);
+    expect(signals.get("/api/discussion/notifications").aborted).toBe(false);
+    for (const { url, response } of held)
+      if (!url.includes(videoId)) {
+        response.writeHead(200, { "Content-Type": "application/json" });
+        response.end(JSON.stringify({ items: [], nextCursor: null }));
+      }
+    expect((await other).ok).toBe(true);
+    expect((await inbox).ok).toBe(true);
+  } finally {
+    client.stop();
+    server.closeAllConnections();
+    await new Promise((resolve) => server.close(resolve));
+  }
+});
diff --git a/Extensions/combined/src/discussion-notifications-socket.spec.js b/Extensions/combined/src/discussion-notifications-socket.spec.js
new file mode 100644
index 0000000..7b4290e
--- /dev/null
+++ b/Extensions/combined/src/discussion-notifications-socket.spec.js
@@ -0,0 +1,136 @@
+import { WebSocketServer } from "ws";
+import { createDiscussionBackground, createConnection } from "./discussion-background";
+
+test("real SignalR events and reconnects fetch durable notifications with fresh hub tickets", async () => {
+  const server = new WebSocketServer({ port: 0, host: "127.0.0.1" });
+  await new Promise((resolve) => server.once("listening", resolve));
+  const profileId = "22222222-2222-4222-8222-222222222222";
+  let peer;
+  const receivedTickets = [];
+  let ticketRequests = 0;
+  let connected;
+  const ready = new Promise((resolve) => {
+    connected = resolve;
+  });
+  server.on("connection", (socket, request) => {
+    peer = socket;
+    receivedTickets.push(request.headers.authorization);
+    expect(request.headers.authorization).toBe(`Bearer hub-ticket-${ticketRequests}`);
+    expect(request.url).toBe("/api/discussion/notifications/hub");
+    socket.on("message", (bytes) => {
+      const message = JSON.parse(bytes.toString().split("\u001e")[0]);
+      if (message.protocol) {
+        socket.send("{}\u001e");
+        connected();
+      }
+    });
+  });
+  let resolveToast;
+  let resolveReconnectedInbox;
+  const reconnectedInbox = new Promise((resolve) => {
+    resolveReconnectedInbox = resolve;
+  });
+  let toasts = 0;
+  const toast = new Promise((resolve) => {
+    resolveToast = resolve;
+  });
+  const area = {
+    get: (keys, callback) => callback({ patreonAuthenticated: true, patreonSessionToken: "account-token" }),
+    set: (values, callback) => callback?.(),
+    remove: (keys, callback) => callback?.(),
+  };
+  const api = {
+    runtime: {
+      id: "extension-id",
+      getURL: (path) => `chrome-extension://extension-id/${path}`,
+      sendMessage: (message, callback) => callback?.(),
+    },
+    storage: { sync: area, local: area },
+    tabs: {
+      query: (query, callback) => callback([{ id: 1, url: "https://www.youtube.com/watch?v=video123456" }]),
+      sendMessage: (id, message, callback) => {
+        if (message.type === "toast") {
+          toasts++;
+          resolveToast(message.data);
+        }
+        if (message.type === "inbox" && message.data.revision === "2") resolveReconnectedInbox(message.data);
+        callback?.();
+      },
+    },
+  };
+  let revision = "0";
+  const notification = {
+    id: "33333333-3333-4333-8333-333333333333",
+    commentId: "11111111-1111-4111-8111-111111111111",
+    type: "reply",
+    read: false,
+    revision: "1",
+    updatedAt: "2026-09-06T10:05:00Z",
+  };
+  const notificationReads = [];
+  const client = createDiscussionBackground({
+    api,
+    voteClient: { ensureRegistered: async () => ({ userId: "unused" }) },
+    settings: { apiOrigin: "https://returnyoutubedislikeapi.com", testMode: false, stateStorageKey: "state" },
+    connectionFactory: (url, tokenFactory) =>
+      createConnection(`http://127.0.0.1:${server.address().port}/api/discussion/notifications/hub`, tokenFactory),
+    fetchImpl: async (url) => {
+      let data;
+      if (url.endsWith("/me"))
+        data = { authenticated: true, profile: { id: profileId, nickname: "Tester" }, canPost: true };
+      else if (url.endsWith("/ticket")) data = { token: `hub-ticket-${++ticketRequests}` };
+      else {
+        notificationReads.push(url);
+        data = {
+          items: revision === "0" ? [] : [notification],
+          unreadCount: revision === "0" ? 0 : 1,
+          revision,
+          nextCursor: null,
+        };
+      }
+      return { ok: true, status: 200, json: async () => data };
+    },
+  });
+  try {
+    await client.refreshSession();
+    await ready;
+    // Let the socket's initial durable catchup complete before sending a new event.
+    await new Promise((resolve) => setTimeout(resolve, 20));
+    const before = notificationReads.length;
+    revision = "1";
+    peer.send(`${JSON.stringify({ type: 1, target: "NotificationsChanged", arguments: [{ revision }] })}\u001e`);
+    expect(await toast).toEqual(notification);
+    expect(notificationReads.length).toBeGreaterThan(before);
+    expect(notificationReads.at(-1)).toContain("afterRevision=0");
+    revision = "2";
+    notification.revision = revision;
+    peer.terminate();
+    const recovered = await reconnectedInbox;
+    expect(recovered.revision).toBe("2");
+    expect(receivedTickets).toEqual(["Bearer hub-ticket-1", "Bearer hub-ticket-2"]);
+    expect(notificationReads.at(-1)).toContain("afterRevision=1");
+    expect(toasts).toBe(1);
+  } finally {
+    client.stop();
+    for (const socket of server.clients) socket.terminate();
+    await new Promise((resolve) => server.close(resolve));
+  }
+});
+
+test("the configured SignalR retry policy stops after four reconnect attempts", async () => {
+  const connection = createConnection(
+    "https://returnyoutubedislikeapi.com/api/discussion/notifications/hub",
+    async () => "ticket",
+  );
+  const policy = connection._reconnectPolicy;
+  expect(
+    [0, 1, 2, 3, 4].map((previousRetryCount) =>
+      policy.nextRetryDelayInMilliseconds({
+        previousRetryCount,
+        elapsedMilliseconds: 0,
+        retryReason: new Error("disconnected"),
+      }),
+    ),
+  ).toEqual([0, 2000, 10000, 30000, null]);
+  await connection.stop();
+});
diff --git a/Extensions/combined/src/discussion/bridge.spec.js b/Extensions/combined/src/discussion/bridge.spec.js
new file mode 100644
index 0000000..48363cb
--- /dev/null
+++ b/Extensions/combined/src/discussion/bridge.spec.js
@@ -0,0 +1,218 @@
+/**
+ * @jest-environment jsdom
+ * @jest-environment-options {"url":"https://www.youtube.com/watch?v=abcdefghijk"}
+ */
+
+const source = require("fs").readFileSync(require("path").join(__dirname, "../../comments-bridge.js"), "utf8");
+const VIDEO = "abcdefghijk";
+let handler;
+
+beforeEach(() => {
+  document.body.replaceChildren();
+  window.history.replaceState({}, "", `/watch?v=${VIDEO}`);
+  delete window[Symbol.for("return-youtube-dislike.discussion-bridge")];
+  const spy = jest.spyOn(document, "addEventListener");
+  window.eval(source);
+  handler = spy.mock.calls.find(([name]) => name === "ryd-discussion-state-request")[1];
+  spy.mockRestore();
+});
+afterEach(() => {
+  document.removeEventListener("ryd-discussion-state-request", handler, true);
+  delete window.ytInitialPlayerResponse;
+});
+
+function state(root) {
+  root.dispatchEvent(new Event("ryd-discussion-state-request"));
+  return JSON.parse(root.getAttribute("data-ryd-discussion-native-state"));
+}
+function watch() {
+  document.body.innerHTML = `<ytd-watch-flexy video-id="${VIDEO}"><ytd-comments></ytd-comments></ytd-watch-flexy>`;
+  const root = document.querySelector("ytd-watch-flexy");
+  root.querySelector("ytd-comments").polymerController = {
+    data: {
+      contents: [
+        {
+          messageRenderer: {
+            text: {
+              runs: [
+                { text: "Комментарии отключены." },
+                {
+                  navigationEndpoint: {
+                    urlEndpoint: { url: "https://support.google.com/youtube/answer/9706180?hl=ru" },
+                  },
+                },
+              ],
+            },
+          },
+        },
+      ],
+    },
+  };
+  return root;
+}
+
+function miniplayerNotice(
+  text,
+  helpUrl = "//support.google.com/youtube/bin/answer.py?answer=9632097&nohelpkit=1&hl=en",
+) {
+  return {
+    miniplayer: {
+      miniplayerRenderer: {
+        playbackMode: "PLAYBACK_MODE_PAUSED_ONLY",
+        minimizedEndpoint: {
+          openPopupAction: {
+            popup: {
+              notificationActionRenderer: {
+                responseText: { simpleText: text },
+                actionButton: {
+                  buttonRenderer: {
+                    command: {
+                      urlEndpoint: { url: helpUrl },
+                      commandMetadata: { webCommandMetadata: { url: helpUrl } },
+                    },
+                  },
+                },
+              },
+            },
+          },
+        },
+      },
+    },
+  };
+}
+
+const ENGLISH_KIDS_NOTICE = "Miniplayer is off for videos made for kids. Tap play to resume";
+
+test("reads disabled watch evidence from the page-owned controller without text matching", () => {
+  expect(state(watch())).toEqual({ videoId: VIDEO, disabled: true, madeForKids: false });
+});
+
+test("only an explicit kids flag for the current video excludes the discussion", () => {
+  const root = watch();
+  window.ytInitialPlayerResponse = { videoDetails: { videoId: "zyxwvutsrqp", isMadeForKids: true } };
+  expect(state(root).madeForKids).toBe(false);
+  window.ytInitialPlayerResponse = {
+    videoDetails: { videoId: VIDEO },
+    microformat: { playerMicroformatRenderer: { isFamilySafe: true } },
+  };
+  expect(state(root).madeForKids).toBe(false);
+  window.ytInitialPlayerResponse.videoDetails.isMadeForKids = true;
+  expect(state(root).madeForKids).toBe(true);
+});
+
+test("recognizes the current video's explicit miniplayer kids notice", () => {
+  const root = watch();
+  window.ytInitialPlayerResponse = {
+    videoDetails: { videoId: VIDEO },
+    playabilityStatus: miniplayerNotice(ENGLISH_KIDS_NOTICE),
+  };
+  expect(state(root).madeForKids).toBe(true);
+  window.ytInitialPlayerResponse.videoDetails.videoId = "zyxwvutsrqp";
+  expect(state(root).madeForKids).toBe(false);
+});
+
+test.each([
+  ["en", "//support.google.com/youtube/bin/answer.py?answer=9632097&nohelpkit=1&hl=en"],
+  ["ru", "//support.google.com/youtube/bin/answer.py?answer=9632097&nohelpkit=1&hl=ru"],
+  ["ru", "https://support.google.com/youtube/answer/9632097?hl=ru"],
+])("uses the current miniplayer's made-for-kids help link independently of %s wording", (language, helpUrl) => {
+  const root = watch();
+  document.documentElement.lang = language;
+  window.ytInitialPlayerResponse = {
+    videoDetails: { videoId: VIDEO },
+    playabilityStatus: miniplayerNotice("Localized miniplayer notice", helpUrl),
+  };
+  expect(state(root).madeForKids).toBe(true);
+  delete window.ytInitialPlayerResponse.playabilityStatus.miniplayer.miniplayerRenderer.minimizedEndpoint
+    .openPopupAction.popup.notificationActionRenderer.actionButton.buttonRenderer.command.urlEndpoint;
+  expect(state(root).madeForKids).toBe(true);
+  window.ytInitialPlayerResponse.playabilityStatus.miniplayer.miniplayerRenderer.playbackMode = "PLAYBACK_MODE_ALLOW";
+  expect(state(root).madeForKids).toBe(false);
+});
+
+test.each([
+  "https://support.google.com/youtube/answer/9706180",
+  "https://support.google.com.example.test/youtube/answer/9632097",
+  "https://support.google.com/youtube/bin/answer.py?answer=9706180",
+  "",
+])("does not infer a kids restriction from miniplayer text with an unrelated or absent help link: %s", (helpUrl) => {
+  const root = watch();
+  window.ytInitialPlayerResponse = {
+    videoDetails: { videoId: VIDEO },
+    playabilityStatus: miniplayerNotice(ENGLISH_KIDS_NOTICE, helpUrl),
+  };
+  expect(state(root).madeForKids).toBe(false);
+});
+
+test("ignores matching miniplayer text in descriptions, recommendations and advertisements", () => {
+  const root = watch();
+  const kids = { videoDetails: { videoId: "zyxwvutsrqp" }, playabilityStatus: miniplayerNotice(ENGLISH_KIDS_NOTICE) };
+  window.ytInitialPlayerResponse = {
+    videoDetails: { videoId: VIDEO, shortDescription: ENGLISH_KIDS_NOTICE },
+    playabilityStatus: miniplayerNotice(
+      "Miniplayer is unavailable. Please try again.",
+      "https://support.google.com/youtube/answer/9706180",
+    ),
+    endscreen: { videos: [kids] },
+    adPlacements: [kids],
+  };
+  expect(state(root).madeForKids).toBe(false);
+});
+
+test("finds a disabled Shorts comment button through its controller model", () => {
+  window.history.replaceState({}, "", `/shorts/${VIDEO}`);
+  document.body.innerHTML = `<ytd-reel-video-renderer video-id="${VIDEO}"><reel-action-bar-view-model></reel-action-bar-view-model></ytd-reel-video-renderer>`;
+  const root = document.querySelector("ytd-reel-video-renderer");
+  root.querySelector("reel-action-bar-view-model").polymerController = {
+    data: {
+      buttonViewModels: [
+        { buttonViewModel: { iconName: "SHORTS_COMMENT", state: "BUTTON_VIEW_MODEL_STATE_DISABLED" } },
+      ],
+    },
+  };
+  expect(state(root)).toEqual({ videoId: VIDEO, disabled: true, madeForKids: false });
+  root.querySelector("reel-action-bar-view-model").polymerController.data.buttonViewModels[0].buttonViewModel.state =
+    "BUTTON_VIEW_MODEL_STATE_ACTIVE";
+  expect(state(root).disabled).toBe(false);
+});
+
+test.each(["isMadeForKids", "madeForKids", "is_made_for_kids"])(
+  "accepts current response and microformat %s flags but ignores unrelated nested videos",
+  (flag) => {
+    const root = watch();
+    window.ytInitialPlayerResponse = {
+      videoDetails: { videoId: VIDEO },
+      endscreen: { videos: [{ videoId: "zyxwvutsrqp", [flag]: true }] },
+      adPlacements: [{ videoDetails: { videoId: "zyxwvutsrqp", [flag]: true } }],
+      microformat: { playerMicroformatRenderer: { recommendations: [{ [flag]: true }] } },
+    };
+    expect(state(root).madeForKids).toBe(false);
+    window.ytInitialPlayerResponse.microformat.playerMicroformatRenderer[flag] = true;
+    expect(state(root).madeForKids).toBe(true);
+    window.ytInitialPlayerResponse.microformat.playerMicroformatRenderer.videoId = "zyxwvutsrqp";
+    expect(state(root).madeForKids).toBe(false);
+    window.ytInitialPlayerResponse[flag] = true;
+    expect(state(root).madeForKids).toBe(true);
+  },
+);
+
+test("does not expose a result for an outgoing Shorts renderer", () => {
+  window.history.replaceState({}, "", `/shorts/${VIDEO}`);
+  document.body.innerHTML = '<ytd-reel-video-renderer video-id="zyxwvutsrqp"></ytd-reel-video-renderer>';
+  expect(state(document.querySelector("ytd-reel-video-renderer"))).toBeNull();
+});
+
+test("recognizes an unmarked current reel by contained player identity while rejecting retained reels", () => {
+  window.history.replaceState({}, "", `/shorts/${VIDEO}`);
+  document.body.innerHTML =
+    "<ytd-reel-video-renderer id='retained'><reel-action-bar-view-model></reel-action-bar-view-model></ytd-reel-video-renderer><ytd-reel-video-renderer id='current'><div id='shorts-player'></div><reel-action-bar-view-model></reel-action-bar-view-model></ytd-reel-video-renderer>";
+  document.getElementById("shorts-player").getVideoData = () => ({ video_id: VIDEO });
+  for (const action of document.querySelectorAll("reel-action-bar-view-model"))
+    action.data = {
+      buttonViewModels: [
+        { buttonViewModel: { iconName: "SHORTS_COMMENT", state: "BUTTON_VIEW_MODEL_STATE_DISABLED" } },
+      ],
+    };
+  expect(state(document.getElementById("retained"))).toBeNull();
+  expect(state(document.getElementById("current"))).toEqual({ videoId: VIDEO, disabled: true, madeForKids: false });
+});
diff --git a/Extensions/combined/src/discussion/client.js b/Extensions/combined/src/discussion/client.js
new file mode 100644
index 0000000..428e576
--- /dev/null
+++ b/Extensions/combined/src/discussion/client.js
@@ -0,0 +1,88 @@
+function runtimeApi() {
+  return typeof chrome !== "undefined" ? chrome.runtime : globalThis.browser?.runtime;
+}
+
+export function requestDiscussion(operation, payload = {}, scope) {
+  return new Promise((resolve, reject) => {
+    const runtime = runtimeApi();
+    if (!runtime?.sendMessage) {
+      reject(Object.assign(new Error("Discussion service unavailable"), { code: "unavailable" }));
+      return;
+    }
+    let settled = false;
+    const finish = (response) => {
+      if (settled) return;
+      settled = true;
+      if (runtime.lastError) {
+        reject(Object.assign(new Error(runtime.lastError.message), { code: "unavailable" }));
+      } else if (response?.ok) {
+        resolve(response.data);
+      } else {
+        reject(Object.assign(new Error(response?.error?.message || "Discussion request failed"), response?.error));
+      }
+    };
+    try {
+      const result = runtime.sendMessage(
+        { message: "ryd_discussion", operation, payload, ...(scope ? { scope } : {}) },
+        finish,
+      );
+      if (result?.then)
+        result.then(finish, (error) => {
+          if (!settled) {
+            settled = true;
+            reject(error);
+          }
+        });
+    } catch (error) {
+      reject(error);
+    }
+  });
+}
+
+const VIDEO_OPERATIONS = new Set([
+  "comments",
+  "replies",
+  "comment",
+  "createComment",
+  "editComment",
+  "deleteComment",
+  "react",
+  "report",
+]);
+
+export function createDiscussionRequestScope(videoId, request = requestDiscussion) {
+  const bytes = new Uint8Array(16);
+  globalThis.crypto.getRandomValues(bytes);
+  bytes[6] = (bytes[6] & 15) | 64;
+  bytes[8] = (bytes[8] & 63) | 128;
+  const hex = [...bytes].map((value) => value.toString(16).padStart(2, "0")).join("");
+  const scope = {
+    id: `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20)}`,
+    videoId,
+  };
+  let cancelled = false;
+  const cancelledError = () => Object.assign(new Error("The video changed"), { code: "navigation_changed" });
+  return {
+    request(operation, payload = {}) {
+      if (cancelled) return Promise.reject(cancelledError());
+      return request(operation, payload, VIDEO_OPERATIONS.has(operation) ? scope : undefined).then((data) => {
+        if (cancelled) throw cancelledError();
+        return data;
+      });
+    },
+    cancel() {
+      if (cancelled) return;
+      cancelled = true;
+      request("cancelScope", {}, scope).catch(() => {});
+    },
+  };
+}
+
+export function subscribeDiscussionEvents(listener) {
+  const event = runtimeApi()?.onMessage;
+  const receive = (message) => {
+    if (message?.message === "ryd_discussion_event") listener(message);
+  };
+  event?.addListener(receive);
+  return () => event?.removeListener(receive);
+}
diff --git a/Extensions/combined/src/discussion/client.spec.js b/Extensions/combined/src/discussion/client.spec.js
new file mode 100644
index 0000000..a76e93c
--- /dev/null
+++ b/Extensions/combined/src/discussion/client.spec.js
@@ -0,0 +1,76 @@
+/** @jest-environment jsdom */
+import { createDiscussionRequestScope, requestDiscussion, subscribeDiscussionEvents } from "./client";
+
+afterEach(() => {
+  delete global.chrome;
+});
+
+test("uses a typed worker envelope and returns only the response data", async () => {
+  const sendMessage = jest.fn((message, done) => done({ ok: true, data: { items: [] } }));
+  global.chrome = { runtime: { sendMessage } };
+  await expect(requestDiscussion("comments", { videoId: "abcdefghijk", sort: "top" })).resolves.toEqual({ items: [] });
+  expect(sendMessage.mock.calls[0][0]).toEqual({
+    message: "ryd_discussion",
+    operation: "comments",
+    payload: { videoId: "abcdefghijk", sort: "top" },
+  });
+});
+
+test("preserves safe server error codes and status for translated feedback", async () => {
+  global.chrome = {
+    runtime: {
+      sendMessage: (_, done) => done({ ok: false, error: { code: "nickname_taken", message: "Taken", status: 409 } }),
+    },
+  };
+  await expect(requestDiscussion("profile", { nickname: "Writer" })).rejects.toMatchObject({
+    code: "nickname_taken",
+    status: 409,
+  });
+});
+
+test("subscribes to discussion-only events and removes its listener", () => {
+  let receive;
+  const removeListener = jest.fn();
+  global.chrome = {
+    runtime: {
+      onMessage: {
+        addListener: (listener) => {
+          receive = listener;
+        },
+        removeListener,
+      },
+    },
+  };
+  const callback = jest.fn();
+  const unsubscribe = subscribeDiscussionEvents(callback);
+  receive({ message: "patreon_status_changed" });
+  expect(callback).not.toHaveBeenCalled();
+  const event = { message: "ryd_discussion_event", type: "inbox", data: { items: [] } };
+  receive(event);
+  expect(callback).toHaveBeenCalledWith(event);
+  unsubscribe();
+  expect(removeListener).toHaveBeenCalledWith(receive);
+});
+
+test("a navigation scope sends cancellation and rejects a response that arrives afterwards", async () => {
+  let complete;
+  const sendMessage = jest.fn((message, done) => {
+    if (message.operation === "comments") complete = done;
+    else done({ ok: true, data: { cancelled: true } });
+  });
+  global.chrome = { runtime: { sendMessage } };
+  const scoped = createDiscussionRequestScope("abcdefghijk");
+  const response = scoped.request("comments", { videoId: "abcdefghijk" });
+  const scope = sendMessage.mock.calls[0][0].scope;
+  scoped.cancel();
+  expect(sendMessage.mock.calls[1][0]).toEqual({
+    message: "ryd_discussion",
+    operation: "cancelScope",
+    payload: {},
+    scope,
+  });
+  complete({ ok: true, data: { items: [] } });
+  await expect(response).rejects.toMatchObject({ code: "navigation_changed" });
+  await expect(scoped.request("comments")).rejects.toMatchObject({ code: "navigation_changed" });
+  expect(sendMessage).toHaveBeenCalledTimes(2);
+});
diff --git a/Extensions/combined/src/discussion/detector.js b/Extensions/combined/src/discussion/detector.js
new file mode 100644
index 0000000..efee49d
--- /dev/null
+++ b/Extensions/combined/src/discussion/detector.js
@@ -0,0 +1,87 @@
+export const NATIVE_STATE_ATTRIBUTE = "data-ryd-discussion-native-state";
+export const NATIVE_STATE_REQUEST = "ryd-discussion-state-request";
+
+export function discussionRoute(url = location.href) {
+  try {
+    const parsed = new URL(url);
+    if (parsed.hostname !== "www.youtube.com") return null;
+    const surface = parsed.pathname === "/watch" ? "watch" : parsed.pathname.startsWith("/shorts/") ? "shorts" : null;
+    const videoId = surface === "shorts" ? parsed.pathname.split("/")[2] : parsed.searchParams.get("v");
+    return surface && /^[A-Za-z0-9_-]{11}$/.test(videoId || "") ? { videoId, surface } : null;
+  } catch {
+    return null;
+  }
+}
+
+export function isVisibleSurface(root) {
+  if (!root?.isConnected || root.closest("[hidden], [aria-hidden='true'], [inert]")) return false;
+  for (let element = root; element; element = element.parentElement) {
+    const style = getComputedStyle(element);
+    if (style.display === "none" || style.visibility === "hidden") return false;
+  }
+  return true;
+}
+
+function nativeState(root) {
+  root.removeAttribute(NATIVE_STATE_ATTRIBUTE);
+  root.dispatchEvent(new Event(NATIVE_STATE_REQUEST, { bubbles: false }));
+  let state;
+  try {
+    state = JSON.parse(root.getAttribute(NATIVE_STATE_ATTRIBUTE));
+  } catch {
+    return null;
+  } finally {
+    root.removeAttribute(NATIVE_STATE_ATTRIBUTE);
+  }
+  return state;
+}
+
+function disabledWatchNotice(root) {
+  return [...root.querySelectorAll("ytd-comments ytd-message-renderer a[href]")].some((anchor) => {
+    try {
+      const url = new URL(anchor.href);
+      return (
+        url.hostname === "support.google.com" && url.pathname === "/youtube/answer/9706180" && isVisibleSurface(anchor)
+      );
+    } catch {
+      return false;
+    }
+  });
+}
+
+export function findDiscussionSurface(route = discussionRoute()) {
+  if (!route) return null;
+  const roots = document.querySelectorAll(
+    route.surface === "watch" ? "ytd-watch-flexy, ytd-watch-grid" : "ytd-reel-video-renderer",
+  );
+  for (const root of roots) {
+    if (!isVisibleSurface(root)) continue;
+    if (route.surface === "shorts") {
+      const rect = root.getBoundingClientRect();
+      if (
+        rect.width <= 0 ||
+        rect.height <= 0 ||
+        rect.bottom <= 0 ||
+        rect.right <= 0 ||
+        rect.top >= innerHeight ||
+        rect.left >= innerWidth
+      )
+        continue;
+    }
+    if (route.surface === "watch" && root.getAttribute("video-id") !== route.videoId) continue;
+    const state = nativeState(root);
+    if (
+      state?.madeForKids === true ||
+      ["is-made-for-kids", "made-for-kids"].some((key) => root.hasAttribute(key) && root.getAttribute(key) !== "false")
+    )
+      continue;
+    const disabled = state?.videoId === route.videoId && state.disabled === true;
+    if (!disabled && !(route.surface === "watch" && disabledWatchNotice(root))) continue;
+    const host =
+      route.surface === "watch"
+        ? root.querySelector("ytd-comments")
+        : root.querySelector("reel-action-bar-view-model, #actions");
+    if (host) return { ...route, root, host };
+  }
+  return null;
+}
diff --git a/Extensions/combined/src/discussion/detector.spec.js b/Extensions/combined/src/discussion/detector.spec.js
new file mode 100644
index 0000000..50d3244
--- /dev/null
+++ b/Extensions/combined/src/discussion/detector.spec.js
@@ -0,0 +1,97 @@
+/** @jest-environment jsdom */
+
+import { discussionRoute, findDiscussionSurface, NATIVE_STATE_ATTRIBUTE, NATIVE_STATE_REQUEST } from "./detector";
+
+const VIDEO = "abcdefghijk";
+let listener;
+
+beforeEach(() => {
+  document.body.replaceChildren();
+  document.documentElement.lang = "en";
+});
+afterEach(() => {
+  if (listener) document.removeEventListener(NATIVE_STATE_REQUEST, listener, true);
+  listener = null;
+});
+
+function watch(videoId = VIDEO) {
+  const root = document.createElement("ytd-watch-flexy");
+  root.setAttribute("video-id", videoId);
+  root.innerHTML = "<ytd-comments></ytd-comments>";
+  document.body.append(root);
+  return root;
+}
+
+function respond(state) {
+  listener = (event) => event.target.setAttribute(NATIVE_STATE_ATTRIBUTE, JSON.stringify(state));
+  document.addEventListener(NATIVE_STATE_REQUEST, listener, true);
+}
+
+test("only supports canonical desktop watch and Shorts routes with a valid identity", () => {
+  expect(discussionRoute(`https://www.youtube.com/watch?v=${VIDEO}`)).toEqual({ videoId: VIDEO, surface: "watch" });
+  expect(discussionRoute(`https://www.youtube.com/shorts/${VIDEO}`)).toEqual({ videoId: VIDEO, surface: "shorts" });
+  for (const url of [
+    "https://www.youtube.com/",
+    "https://www.youtube.com/watch?v=oops",
+    `https://m.youtube.com/watch?v=${VIDEO}`,
+    `https://www.youtube.com.evil.test/watch?v=${VIDEO}`,
+  ])
+    expect(discussionRoute(url)).toBeNull();
+});
+
+test.each(["Comments are turned off.", "Комментарии отключены."])(
+  "recognizes the native disabled help endpoint independent of text: %s",
+  (text) => {
+    const root = watch();
+    root.querySelector("ytd-comments").innerHTML =
+      `<ytd-message-renderer><span>${text}</span><a href="https://support.google.com/youtube/answer/9706180?hl=ru">Подробнее</a></ytd-message-renderer>`;
+    expect(findDiscussionSurface({ videoId: VIDEO, surface: "watch" })?.root).toBe(root);
+  },
+);
+
+test("missing comments and generic messages never count as disabled", () => {
+  const root = watch();
+  root.querySelector("ytd-comments").innerHTML = "<ytd-message-renderer>Loading comments</ytd-message-renderer>";
+  expect(findDiscussionSurface({ videoId: VIDEO, surface: "watch" })).toBeNull();
+});
+
+test("accepts positive native disabled evidence when kids status is unknown", () => {
+  const root = watch();
+  respond({ videoId: VIDEO, disabled: true });
+  expect(findDiscussionSurface({ videoId: VIDEO, surface: "watch" })?.host).toBe(root.querySelector("ytd-comments"));
+  expect(root.hasAttribute(NATIVE_STATE_ATTRIBUTE)).toBe(false);
+});
+
+test("positive made-for-kids proof overrides disabled proof and help link", () => {
+  watch();
+  respond({ videoId: VIDEO, disabled: true, madeForKids: true });
+  expect(findDiscussionSurface({ videoId: VIDEO, surface: "watch" })).toBeNull();
+});
+
+test("ignores stale hidden roots and stale bridge identity", () => {
+  const hidden = watch();
+  hidden.hidden = true;
+  watch("zyxwvutsrqp");
+  respond({ videoId: VIDEO, disabled: true });
+  expect(findDiscussionSurface({ videoId: VIDEO, surface: "watch" })).toBeNull();
+  hidden.hidden = false;
+  document.removeEventListener(NATIVE_STATE_REQUEST, listener, true);
+  respond({ videoId: "zyxwvutsrqp", disabled: true });
+  expect(findDiscussionSurface({ videoId: VIDEO, surface: "watch" })).toBeNull();
+});
+
+test("Shorts requires a current native disabled state and action surface", () => {
+  document.body.innerHTML =
+    "<ytd-reel-video-renderer is-active><reel-action-bar-view-model></reel-action-bar-view-model></ytd-reel-video-renderer>";
+  document.querySelector("ytd-reel-video-renderer").getBoundingClientRect = () => ({
+    width: 400,
+    height: 700,
+    top: 0,
+    left: 0,
+    bottom: 700,
+    right: 400,
+  });
+  expect(findDiscussionSurface({ videoId: VIDEO, surface: "shorts" })).toBeNull();
+  respond({ videoId: VIDEO, disabled: true, madeForKids: false });
+  expect(findDiscussionSurface({ videoId: VIDEO, surface: "shorts" })?.host.tagName).toBe("REEL-ACTION-BAR-VIEW-MODEL");
+});
diff --git a/Extensions/combined/src/discussion/dom.js b/Extensions/combined/src/discussion/dom.js
new file mode 100644
index 0000000..9eb7037
--- /dev/null
+++ b/Extensions/combined/src/discussion/dom.js
@@ -0,0 +1,72 @@
+export function element(tag, className, text) {
+  const node = document.createElement(tag);
+  if (className) node.className = className;
+  if (text != null) node.textContent = text;
+  return node;
+}
+
+export function button(text, onClick, className = "ryd-discussion-button") {
+  const node = element("button", className, text);
+  node.type = "button";
+  if (onClick) node.addEventListener("click", onClick);
+  return node;
+}
+
+export function statusNode() {
+  const node = element("p", "ryd-discussion-status");
+  node.setAttribute("role", "status");
+  node.setAttribute("aria-live", "polite");
+  return node;
+}
+
+export function isDiscussionCommentId(value) {
+  return /^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$/i.test(value || "");
+}
+
+export function discussionLinkTarget(value = location.href) {
+  try {
+    const url = new URL(value);
+    if (url.protocol !== "https:" || url.hostname !== "www.youtube.com") return null;
+    const videoId =
+      url.pathname === "/watch"
+        ? url.searchParams.get("v")
+        : /^\/shorts\/([A-Za-z0-9_-]{11})\/?$/.exec(url.pathname)?.[1];
+    const commentId = new URLSearchParams(url.hash.slice(1)).get("rydComment") || url.searchParams.get("rydComment");
+    return /^[A-Za-z0-9_-]{11}$/.test(videoId || "") && isDiscussionCommentId(commentId)
+      ? { videoId, commentId }
+      : null;
+  } catch {
+    return null;
+  }
+}
+
+export function threadUrl(notification) {
+  if (!/^[A-Za-z0-9_-]{11}$/.test(notification?.videoId || "") || !isDiscussionCommentId(notification?.commentId))
+    return null;
+  const url = new URL("https://www.youtube.com/watch");
+  url.searchParams.set("v", notification.videoId);
+  url.hash = new URLSearchParams({ rydComment: notification.commentId }).toString();
+  return url.href;
+}
+
+export function shortDate(value, language) {
+  const date = new Date(value);
+  return Number.isNaN(date.getTime())
+    ? ""
+    : date.toLocaleDateString(language, { month: "short", day: "numeric", year: "numeric" });
+}
+
+export function thumbIcon(dislike = false) {
+  const icon = document.createElementNS("http://www.w3.org/2000/svg", "svg");
+  icon.setAttribute("viewBox", "0 0 24 24");
+  icon.setAttribute("aria-hidden", "true");
+  icon.classList.add("ryd-discussion-thumb");
+  if (dislike) icon.classList.add("is-down");
+  const path = document.createElementNS("http://www.w3.org/2000/svg", "path");
+  path.setAttribute(
+    "d",
+    "M7 10v12H2V10h5Zm2 12V10l5-8 1.1.4c.9.4 1.4 1.4 1.2 2.4L15.5 9H20a2 2 0 0 1 2 2v2l-3 9H9ZM3.5 11.5v9H5.5v-9h-2Zm7 9h7.4l2.6-7.7V11a.5.5 0 0 0-.5-.5h-6.3l1.1-6a.8.8 0 0 0-.2-.6L10.5 10.4v10.1Z",
+  );
+  icon.append(path);
+  return icon;
+}
diff --git a/Extensions/combined/src/discussion/dom.spec.js b/Extensions/combined/src/discussion/dom.spec.js
new file mode 100644
index 0000000..93bde4e
--- /dev/null
+++ b/Extensions/combined/src/discussion/dom.spec.js
@@ -0,0 +1,37 @@
+/** @jest-environment jsdom */
+
+import { discussionLinkTarget, isDiscussionCommentId, threadUrl } from "./dom";
+
+const videoId = "abcdefghijk";
+const commentId = "11111111-1111-4111-8111-111111111111";
+
+test("notification links carry a validated fragment through a native video URL", () => {
+  const url = threadUrl({ videoId, commentId });
+  expect(new URL(url).searchParams.has("rydComment")).toBe(false);
+  expect(discussionLinkTarget(url)).toEqual({ videoId, commentId });
+  expect(discussionLinkTarget(`https://www.youtube.com/shorts/${videoId}#rydComment=${commentId}`)).toEqual({
+    videoId,
+    commentId,
+  });
+  expect(discussionLinkTarget(`https://www.youtube.com/watch?v=${videoId}&rydComment=${commentId}`)).toEqual({
+    videoId,
+    commentId,
+  });
+});
+
+test.each([
+  `https://example.com/watch?v=${videoId}#rydComment=${commentId}`,
+  `http://www.youtube.com/watch?v=${videoId}#rydComment=${commentId}`,
+  `https://www.youtube.com/feed?v=${videoId}#rydComment=${commentId}`,
+  `https://www.youtube.com/watch?v=short#rydComment=${commentId}`,
+  `https://www.youtube.com/watch?v=${videoId}#rydComment=${"-".repeat(36)}`,
+  "javascript:alert(1)",
+])("rejects an invalid discussion destination: %s", (url) => {
+  expect(discussionLinkTarget(url)).toBeNull();
+});
+
+test("UUID validation rejects same-length malformed identifiers", () => {
+  expect(isDiscussionCommentId(commentId)).toBe(true);
+  expect(isDiscussionCommentId("1".repeat(36))).toBe(false);
+  expect(threadUrl({ videoId, commentId: "-".repeat(36) })).toBeNull();
+});
diff --git a/Extensions/combined/src/discussion/inbox.js b/Extensions/combined/src/discussion/inbox.js
new file mode 100644
index 0000000..563ca01
--- /dev/null
+++ b/Extensions/combined/src/discussion/inbox.js
@@ -0,0 +1,174 @@
+import { requestDiscussion } from "./client";
+import { discussionText as t, discussionError, discussionLanguage } from "./localize";
+import { element, button, statusNode, threadUrl, shortDate } from "./dom";
+
+export function notificationText(notification) {
+  return notification.type === "reply"
+    ? t("notificationReply", [notification.actorNickname || t("someone")])
+    : notification.likeCount > 1
+      ? t("notificationLikes", [notification.likeCount])
+      : t("notificationLike");
+}
+
+export function createDiscussionInbox({ request = requestDiscussion, authenticated = true } = {}) {
+  const node = element("section", "ryd-discussion-inbox");
+  const heading = element("div", "ryd-discussion-toolbar");
+  heading.append(element("h3", "ryd-discussion-subtitle", t("notifications")));
+  const readAll = button(t("markAllRead"), async () => {
+    readAll.disabled = true;
+    try {
+      await request("readNotifications", { all: true });
+      await load();
+    } catch (error) {
+      status.textContent = discussionError(error);
+    } finally {
+      readAll.disabled = false;
+    }
+  });
+  heading.append(readAll);
+  const list = element("div", "ryd-discussion-inbox-list");
+  const status = statusNode();
+  const more = button(t("more"), () => load(true));
+  more.hidden = true;
+  node.append(heading, status, list, more);
+  let items = [];
+  let cursor = null;
+  let disposed = false;
+  let generation = 0;
+  let hasPage = false;
+  let accountId = null;
+
+  function render() {
+    list.replaceChildren();
+    readAll.hidden = !authenticated || !items.some((item) => !item.read);
+    if (!authenticated) {
+      status.textContent = t("signedOutInbox");
+      more.hidden = true;
+      return;
+    }
+    status.textContent = items.length ? "" : t("notificationEmpty");
+    for (const item of items) {
+      const row = element("article", `ryd-discussion-notification${item.read ? "" : " is-unread"}`);
+      row.dataset.notificationId = item.id;
+      const link = element("a", "ryd-discussion-notification-link", notificationText(item));
+      const url = threadUrl(item);
+      if (url) {
+        link.href = url;
+        link.target = "_blank";
+        link.rel = "noopener noreferrer";
+        link.addEventListener("click", () => {
+          request("readNotifications", { ids: [item.id] })
+            .then(() => {
+              item.read = true;
+              render();
+            })
+            .catch(() => {});
+        });
+      }
+      const date = element("time", "ryd-discussion-meta", shortDate(item.createdAt, discussionLanguage()));
+      date.dateTime = item.createdAt;
+      row.append(link, date);
+      if (!item.read)
+        row.append(
+          button(t("markRead"), async (event) => {
+            event.currentTarget.disabled = true;
+            try {
+              await request("readNotifications", { ids: [item.id] });
+              item.read = true;
+              render();
+            } catch (error) {
+              status.textContent = discussionError(error);
+              event.target.disabled = false;
+            }
+          }),
+        );
+      list.append(row);
+    }
+    more.hidden = !cursor;
+  }
+
+  async function load(append = false) {
+    if (disposed || !authenticated) {
+      render();
+      return;
+    }
+    const current = ++generation;
+    status.textContent = t("loading");
+    more.disabled = true;
+    try {
+      const result = await request("notifications", append && cursor ? { cursor } : {});
+      if (disposed || current !== generation) return;
+      const combined = append ? [...items, ...(result.items || [])] : result.items || [];
+      items = [...new Map(combined.map((item) => [item.id, item])).values()];
+      cursor = result.nextCursor;
+      hasPage = true;
+      render();
+    } catch (error) {
+      if (!disposed && current === generation) status.textContent = discussionError(error);
+    } finally {
+      more.disabled = false;
+    }
+  }
+
+  return {
+    node,
+    load,
+    setSession(session) {
+      authenticated = session?.authenticated === true;
+      const nextId = authenticated ? session.profile?.id || null : null;
+      generation++;
+      if (!authenticated || nextId !== accountId) {
+        items = [];
+        cursor = null;
+        hasPage = false;
+      }
+      accountId = nextId;
+      render();
+    },
+    update(inbox, { live = false } = {}) {
+      if (disposed || !authenticated) return;
+      generation++;
+      if (live) {
+        items = [...new Map([...items, ...(inbox?.items || [])].map((item) => [item.id, item])).values()].sort((a, b) =>
+          String(b.updatedAt || b.createdAt).localeCompare(String(a.updatedAt || a.createdAt)),
+        );
+      } else {
+        items = inbox?.items || [];
+      }
+      if (!live || !hasPage) cursor = inbox?.nextCursor;
+      hasPage = true;
+      render();
+    },
+    destroy() {
+      disposed = true;
+      generation++;
+      node.remove();
+    },
+  };
+}
+
+export function showDiscussionToast(notification) {
+  document.querySelector(".ryd-discussion-toast")?.remove();
+  const toast = element("aside", "ryd-discussion-toast");
+  toast.setAttribute("role", "status");
+  toast.setAttribute("aria-live", "polite");
+  const copy = element("div");
+  copy.append(element("strong", "", t("title")), element("p", "", notificationText(notification)));
+  const url = threadUrl(notification);
+  if (url) {
+    const link = element("a", "ryd-discussion-button", t("view"));
+    link.href = url;
+    link.dataset.notificationId = notification.id;
+    link.addEventListener("click", () =>
+      requestDiscussion("readNotifications", { ids: [notification.id] }).catch(() => {}),
+    );
+    copy.append(link);
+  }
+  toast.append(
+    copy,
+    button("×", () => toast.remove(), "ryd-discussion-close"),
+  );
+  toast.lastChild.setAttribute("aria-label", t("close"));
+  document.body.append(toast);
+  setTimeout(() => toast.remove(), 10000);
+}
diff --git a/Extensions/combined/src/discussion/inbox.spec.js b/Extensions/combined/src/discussion/inbox.spec.js
new file mode 100644
index 0000000..7f77c6f
--- /dev/null
+++ b/Extensions/combined/src/discussion/inbox.spec.js
@@ -0,0 +1,101 @@
+/** @jest-environment jsdom */
+
+import { createDiscussionInbox, notificationText } from "./inbox";
+import { threadUrl } from "./dom";
+
+const ID = "11111111-1111-4111-8111-111111111111";
+const notification = {
+  id: ID,
+  videoId: "abcdefghijk",
+  commentId: ID,
+  type: "reply",
+  actorNickname: "Reader",
+  createdAt: "2026-09-01T00:00:00Z",
+  read: false,
+};
+let inbox;
+beforeEach(() => {
+  document.body.replaceChildren();
+  document.documentElement.lang = "en";
+});
+afterEach(() => inbox?.destroy());
+
+test("builds a canonical discussion link rather than accepting an arbitrary destination", () => {
+  expect(threadUrl(notification)).toBe(`https://www.youtube.com/watch?v=abcdefghijk#rydComment=${ID}`);
+  expect(threadUrl({ ...notification, videoId: "javascript:alert(1)" })).toBeNull();
+});
+
+test("renders nicknames as text and identifies each notification for inbox actions", async () => {
+  const request = jest
+    .fn()
+    .mockResolvedValue({ items: [{ ...notification, actorNickname: "<img src=x>" }], nextCursor: null });
+  inbox = createDiscussionInbox({ request });
+  document.body.append(inbox.node);
+  await inbox.load();
+  expect(inbox.node.querySelector("img")).toBeNull();
+  expect(inbox.node.querySelector("[data-notification-id]").dataset.notificationId).toBe(ID);
+  expect(inbox.node.textContent).toContain("<img src=x>");
+});
+
+test("logout prevents an older inbox response from exposing the previous account's rows", async () => {
+  let resolve;
+  const request = jest.fn(
+    () =>
+      new Promise((done) => {
+        resolve = done;
+      }),
+  );
+  inbox = createDiscussionInbox({ request });
+  document.body.append(inbox.node);
+  const pending = inbox.load();
+  inbox.setSession({ authenticated: false });
+  resolve({ items: [notification] });
+  await pending;
+  expect(inbox.node.querySelector("[data-notification-id]")).toBeNull();
+});
+
+test("a newer shared inbox broadcast cannot be overwritten by an older pending read", async () => {
+  let resolve;
+  const request = jest.fn(
+    () =>
+      new Promise((done) => {
+        resolve = done;
+      }),
+  );
+  inbox = createDiscussionInbox({ request });
+  document.body.append(inbox.node);
+  const pending = inbox.load();
+  inbox.update({ items: [notification], unreadCount: 1 });
+  resolve({ items: [], unreadCount: 0 });
+  await pending;
+  expect(inbox.node.querySelector("[data-notification-id]")).not.toBeNull();
+});
+
+test("anonymous likes notifications do not expose a reaction identity", () => {
+  document.documentElement.lang = "ru";
+  expect(notificationText({ type: "likes", actorNickname: null })).toBe("Кому-то понравился ваш комментарий");
+});
+
+test("a live update preserves loaded history and the remaining pagination cursor", async () => {
+  const older = { ...notification, id: "22222222-2222-4222-8222-222222222222", createdAt: "2026-08-31T00:00:00Z" };
+  const newest = { ...notification, id: "33333333-3333-4333-8333-333333333333", createdAt: "2026-09-02T00:00:00Z" };
+  const request = jest.fn().mockResolvedValue({ items: [older], nextCursor: "oldest-page" });
+  inbox = createDiscussionInbox({ request });
+  inbox.update({ items: [notification], nextCursor: "older-page" });
+  await inbox.load(true);
+  inbox.update({ items: [newest, notification], nextCursor: "older-page" }, { live: true });
+  expect([...inbox.node.querySelectorAll("[data-notification-id]")].map((node) => node.dataset.notificationId)).toEqual(
+    [newest.id, notification.id, older.id],
+  );
+  await inbox.load(true);
+  expect(request).toHaveBeenLastCalledWith("notifications", { cursor: "oldest-page" });
+});
+
+test("an account replacement clears old rows and pagination even without an intervening anonymous event", () => {
+  inbox = createDiscussionInbox();
+  inbox.setSession({ authenticated: true, profile: { id: "first-account" } });
+  inbox.update({ items: [notification], nextCursor: "older-page" });
+  inbox.setSession({ authenticated: true, profile: { id: "second-account" } });
+  expect(inbox.node.querySelector("[data-notification-id]")).toBeNull();
+  expect(inbox.node.lastChild.hidden).toBe(true);
+});
diff --git a/Extensions/combined/src/discussion/index.js b/Extensions/combined/src/discussion/index.js
new file mode 100644
index 0000000..0827488
--- /dev/null
+++ b/Extensions/combined/src/discussion/index.js
@@ -0,0 +1,284 @@
+import { createDiscussionRequestScope, requestDiscussion, subscribeDiscussionEvents } from "./client";
+import { discussionRoute, findDiscussionSurface } from "./detector";
+import { discussionLanguage, discussionText as t } from "./localize";
+import { createDiscussionPanel } from "./panel";
+import { showDiscussionToast } from "./inbox";
+import { button, element, discussionLinkTarget, isDiscussionCommentId } from "./dom";
+
+let installed = null;
+
+export function initDiscussion({ request = requestDiscussion } = {}) {
+  if (installed) return installed;
+  let panel = null;
+  let panelScope = null;
+  let surface = null;
+  let launcher = null;
+  let backdrop = null;
+  let drawerOpenVideoId = null;
+  let focusedCommentKey = null;
+  let session = { authenticated: false, profile: null, canPost: false, isModerator: false };
+  let capabilities = {};
+  let inbox = null;
+  let disposed = false;
+  let navigationPending = false;
+  let navigationOrigin = null;
+  let language = discussionLanguage();
+  let scheduled = null;
+  let sessionGeneration = 0;
+
+  const bridge = document.createElement("script");
+  bridge.src = chrome.runtime.getURL("comments-bridge.js");
+  bridge.onload = () => {
+    bridge.remove();
+    refresh();
+  };
+  bridge.onerror = () => {
+    bridge.remove();
+    refresh();
+  };
+  (document.head || document.documentElement).append(bridge);
+
+  function clear() {
+    focusedCommentKey = null;
+    panelScope?.cancel();
+    panelScope = null;
+    panel?.destroy();
+    panel = null;
+    launcher?.remove();
+    launcher = null;
+    backdrop?.remove();
+    backdrop = null;
+    surface = null;
+  }
+
+  function closeDrawer() {
+    drawerOpenVideoId = null;
+    if (!panel || surface?.surface !== "shorts") return;
+    panel.root.hidden = true;
+    if (backdrop) backdrop.hidden = true;
+    launcher?.setAttribute("aria-expanded", "false");
+    launcher?.focus();
+  }
+
+  function openDrawer() {
+    if (!panel || surface?.surface !== "shorts") return;
+    drawerOpenVideoId = surface.videoId;
+    panel.root.hidden = false;
+    backdrop.hidden = false;
+    launcher.setAttribute("aria-expanded", "true");
+    panel.root.focus();
+  }
+
+  async function focusLinkedComment(target, force = false) {
+    if (!target || !panel || surface?.videoId !== target.videoId || discussionRoute()?.videoId !== target.videoId)
+      return;
+    const key = `${target.videoId}:${target.commentId}`;
+    if (!force && focusedCommentKey === key) return;
+    focusedCommentKey = key;
+    if (surface.surface === "shorts") openDrawer();
+    await panel.focusComment(target.commentId);
+  }
+
+  function notificationLinkClick(event) {
+    if (
+      event.defaultPrevented ||
+      event.button !== 0 ||
+      event.ctrlKey ||
+      event.metaKey ||
+      event.shiftKey ||
+      event.altKey
+    )
+      return;
+    const anchor = event.target?.closest?.(".ryd-discussion-notification-link, .ryd-discussion-toast a[href]");
+    if (!anchor || anchor.hasAttribute("download") || (anchor.target && anchor.target !== "_self")) return;
+    const target = discussionLinkTarget(anchor.href);
+    if (!target || !panel || surface?.videoId !== target.videoId || discussionRoute()?.videoId !== target.videoId)
+      return;
+    event.preventDefault();
+    event.stopPropagation();
+    const url = new URL(location.href);
+    url.searchParams.delete("rydComment");
+    url.hash = new URLSearchParams({ rydComment: target.commentId }).toString();
+    history.replaceState(history.state, "", url.href);
+    const notificationId = anchor.closest("[data-notification-id]")?.dataset.notificationId;
+    if (isDiscussionCommentId(notificationId)) request("readNotifications", { ids: [notificationId] }).catch(() => {});
+    focusLinkedComment(target, true);
+  }
+
+  async function refresh() {
+    if (disposed) return;
+    const route = discussionRoute();
+    const linkedTarget = discussionLinkTarget();
+    if (route?.surface !== "shorts" || route.videoId !== drawerOpenVideoId) drawerOpenVideoId = null;
+    if (navigationPending && route?.videoId === navigationOrigin) return;
+    if (navigationPending && route?.videoId !== navigationOrigin) navigationPending = false;
+    const nextLanguage = discussionLanguage();
+    if (nextLanguage !== language) {
+      language = nextLanguage;
+      clear();
+    }
+    const next = capabilities.enabled === true ? findDiscussionSurface(route) : null;
+    if (!next) {
+      clear();
+      return;
+    }
+    if (
+      surface?.videoId === next.videoId &&
+      surface?.root === next.root &&
+      surface?.host === next.host &&
+      panel?.root.isConnected &&
+      (!launcher || launcher.isConnected)
+    ) {
+      await focusLinkedComment(linkedTarget);
+      return;
+    }
+    clear();
+    surface = next;
+    panelScope = createDiscussionRequestScope(next.videoId, request);
+    panel = createDiscussionPanel({
+      videoId: next.videoId,
+      surface: next.surface,
+      session,
+      capabilities,
+      request: panelScope.request,
+      ...(next.surface === "shorts" ? { onClose: closeDrawer } : {}),
+    });
+    if (inbox) panel.setInbox(inbox);
+    if (next.surface === "watch") {
+      next.host.insertAdjacentElement("afterend", panel.root);
+    } else {
+      launcher = button("RYD", openDrawer, "ryd-discussion-launcher");
+      launcher.id = "ryd-discussion-launcher";
+      launcher.dataset.videoId = next.videoId;
+      launcher.setAttribute("aria-label", t("open"));
+      launcher.setAttribute("title", t("open"));
+      launcher.setAttribute("aria-haspopup", "dialog");
+      launcher.setAttribute("aria-expanded", "false");
+      next.host.insertAdjacentElement("afterend", launcher);
+      backdrop = element("div", "ryd-discussion-backdrop");
+      backdrop.hidden = true;
+      backdrop.addEventListener("click", closeDrawer);
+      panel.root.hidden = true;
+      document.body.append(backdrop, panel.root);
+      if (drawerOpenVideoId === next.videoId) openDrawer();
+    }
+    const currentPanel = panel;
+    await currentPanel.load();
+    if (currentPanel !== panel || disposed) return;
+    await focusLinkedComment(discussionLinkTarget() || linkedTarget);
+  }
+
+  function schedule() {
+    if (disposed || scheduled) return;
+    scheduled = setTimeout(() => {
+      scheduled = null;
+      refresh();
+    }, 150);
+  }
+  function navigationStart() {
+    drawerOpenVideoId = null;
+    navigationPending = true;
+    navigationOrigin = discussionRoute()?.videoId;
+    clear();
+  }
+  function navigationFinish() {
+    navigationPending = false;
+    refresh();
+  }
+  function keyboard(event) {
+    if (!panel || surface?.surface !== "shorts" || panel.root.hidden) return;
+    if (event.key === "Escape") {
+      event.preventDefault();
+      event.stopPropagation();
+      closeDrawer();
+    }
+    if (event.key === "Tab") {
+      const focusable = [...panel.root.querySelectorAll("button, input, textarea, select, a[href]")].filter(
+        (node) => !node.disabled && !node.closest("[hidden]"),
+      );
+      const first = focusable[0];
+      const last = focusable[focusable.length - 1];
+      if (event.shiftKey && (document.activeElement === first || document.activeElement === panel.root)) {
+        event.preventDefault();
+        last?.focus();
+      } else if (!event.shiftKey && document.activeElement === last) {
+        event.preventDefault();
+        first?.focus();
+      }
+    }
+  }
+  const observer = new MutationObserver(schedule);
+  observer.observe(document.documentElement, {
+    childList: true,
+    subtree: true,
+    attributes: true,
+    attributeFilter: ["lang", "video-id", "is-active", "hidden"],
+  });
+  document.addEventListener("yt-navigate-start", navigationStart);
+  document.addEventListener("yt-navigate-finish", navigationFinish);
+  window.addEventListener("pagehide", navigationStart);
+  window.addEventListener("pageshow", navigationFinish);
+  window.addEventListener("hashchange", refresh);
+  window.addEventListener("popstate", refresh);
+  document.addEventListener("click", notificationLinkClick, true);
+  document.addEventListener("keydown", keyboard, true);
+  const timer = setInterval(refresh, 1000);
+  const unsubscribe = subscribeDiscussionEvents((event) => {
+    if (disposed) return;
+    if (event.type === "session") {
+      sessionGeneration++;
+      session = event.data;
+      panel?.setSession(session);
+      if (!session?.authenticated) {
+        inbox = null;
+        document.querySelector(".ryd-discussion-toast")?.remove();
+      }
+    }
+    if (event.type === "inbox") {
+      inbox = event.data;
+      panel?.setInbox(inbox);
+    }
+    if (event.type === "toast" && session.authenticated) showDiscussionToast(event.data);
+  });
+  const initialSession = sessionGeneration;
+  request("session")
+    .then((value) => {
+      if (!disposed && initialSession === sessionGeneration) {
+        session = value;
+        panel?.setSession(session);
+      }
+    })
+    .catch(() => {});
+  request("capabilities")
+    .then((value) => {
+      if (!disposed) {
+        capabilities = value || {};
+        refresh();
+      }
+    })
+    .catch(() => {});
+  refresh();
+  installed = {
+    refresh,
+    destroy() {
+      disposed = true;
+      drawerOpenVideoId = null;
+      clear();
+      clearInterval(timer);
+      clearTimeout(scheduled);
+      observer.disconnect();
+      unsubscribe();
+      bridge.remove();
+      document.removeEventListener("yt-navigate-start", navigationStart);
+      document.removeEventListener("yt-navigate-finish", navigationFinish);
+      window.removeEventListener("pagehide", navigationStart);
+      window.removeEventListener("pageshow", navigationFinish);
+      window.removeEventListener("hashchange", refresh);
+      window.removeEventListener("popstate", refresh);
+      document.removeEventListener("click", notificationLinkClick, true);
+      document.removeEventListener("keydown", keyboard, true);
+      installed = null;
+    },
+  };
+  return installed;
+}
diff --git a/Extensions/combined/src/discussion/index.spec.js b/Extensions/combined/src/discussion/index.spec.js
new file mode 100644
index 0000000..f84b21e
--- /dev/null
+++ b/Extensions/combined/src/discussion/index.spec.js
@@ -0,0 +1,349 @@
+/**
+ * @jest-environment jsdom
+ * @jest-environment-options {"url":"https://www.youtube.com/watch?v=abcdefghijk"}
+ */
+
+import { initDiscussion } from "./index";
+import { NATIVE_STATE_REQUEST, NATIVE_STATE_ATTRIBUTE } from "./detector";
+import { threadUrl } from "./dom";
+
+const VIDEO = "abcdefghijk";
+const OTHER = "zyxwvutsrqp";
+const ROOT_COMMENT = "11111111-1111-4111-8111-111111111111";
+const REPLY_COMMENT = "22222222-2222-4222-8222-222222222222";
+const flush = async () => {
+  for (let i = 0; i < 15; i++) await Promise.resolve();
+};
+let feature;
+let listener;
+let eventListener;
+
+beforeEach(() => {
+  jest.useFakeTimers();
+  document.body.innerHTML = `<ytd-watch-flexy video-id="${VIDEO}"><ytd-comments></ytd-comments></ytd-watch-flexy>`;
+  window.history.replaceState({}, "", `/watch?v=${VIDEO}`);
+  document.documentElement.lang = "en";
+  global.chrome = {
+    runtime: {
+      getURL: (path) => `chrome-extension://test/${path}`,
+      onMessage: {
+        addListener: (value) => {
+          eventListener = value;
+        },
+        removeListener: jest.fn(),
+      },
+    },
+  };
+  listener = (event) =>
+    event.target.setAttribute(
+      NATIVE_STATE_ATTRIBUTE,
+      JSON.stringify({ videoId: event.target.getAttribute("video-id"), disabled: true, madeForKids: false }),
+    );
+  document.addEventListener(NATIVE_STATE_REQUEST, listener, true);
+});
+afterEach(() => {
+  feature?.destroy();
+  document.removeEventListener(NATIVE_STATE_REQUEST, listener, true);
+  jest.useRealTimers();
+  delete global.chrome;
+});
+
+function request(operation) {
+  if (operation === "session") return Promise.resolve({ authenticated: false, canPost: false, profile: null });
+  if (operation === "capabilities") return Promise.resolve({ enabled: true });
+  return Promise.resolve({ items: [], nextCursor: null });
+}
+
+function shortsFixture(videoId = VIDEO) {
+  window.history.replaceState({}, "", `/shorts/${videoId}`);
+  document.body.innerHTML = `<ytd-reel-video-renderer video-id="${videoId}"><reel-action-bar-view-model></reel-action-bar-view-model></ytd-reel-video-renderer>`;
+  const reel = document.querySelector("ytd-reel-video-renderer");
+  reel.getBoundingClientRect = () => ({ width: 400, height: 600, top: 0, left: 0, right: 400, bottom: 600 });
+  return reel;
+}
+
+function linkRequest(operation, payload) {
+  if (operation === "session")
+    return Promise.resolve({ authenticated: true, canPost: false, profile: { id: "reader" } });
+  if (operation === "comment")
+    return Promise.resolve({
+      id: payload.id,
+      videoId: VIDEO,
+      parentId: payload.id === REPLY_COMMENT ? ROOT_COMMENT : null,
+      replyToId: payload.id === REPLY_COMMENT ? ROOT_COMMENT : null,
+      author: { id: "author", nickname: "Writer" },
+      text: payload.id === REPLY_COMMENT ? "Linked reply" : "Root comment",
+      createdAt: "2026-09-01T00:00:00Z",
+      replyCount: 1,
+      likes: 0,
+      dislikes: 0,
+    });
+  return request(operation);
+}
+
+function notificationAnchor({ target = "", videoId = VIDEO } = {}) {
+  const toast = document.createElement("aside");
+  toast.className = "ryd-discussion-toast";
+  const anchor = document.createElement("a");
+  anchor.href = threadUrl({ videoId, commentId: REPLY_COMMENT });
+  anchor.target = target;
+  anchor.dataset.notificationId = ROOT_COMMENT;
+  toast.append(anchor);
+  document.body.append(toast);
+  return anchor;
+}
+
+test("repeated native observer checks mount exactly one panel and fetch once", async () => {
+  const call = jest.fn(request);
+  feature = initDiscussion({ request: call });
+  await flush();
+  jest.advanceTimersByTime(4000);
+  await flush();
+  expect(document.querySelectorAll("#ryd-discussion-panel")).toHaveLength(1);
+  expect(call.mock.calls.filter(([operation]) => operation === "comments")).toHaveLength(1);
+});
+
+test.each(["pending", "unavailable", "disabled"])(
+  "%s capabilities leave the native comments page untouched",
+  async (state) => {
+    const native = document.body.innerHTML;
+    const call = jest.fn((operation) => {
+      if (operation !== "capabilities") return request(operation);
+      if (state === "pending") return new Promise(() => {});
+      if (state === "unavailable") return Promise.reject(Object.assign(new Error("Not found"), { status: 404 }));
+      return Promise.resolve({ enabled: false });
+    });
+    feature = initDiscussion({ request: call });
+    await flush();
+    jest.advanceTimersByTime(4000);
+    await flush();
+    expect(document.body.innerHTML).toBe(native);
+    expect(call.mock.calls.some(([operation]) => operation === "comments")).toBe(false);
+  },
+);
+
+test("an enabled service still shows subsequent comment request failures", async () => {
+  feature = initDiscussion({
+    request: (operation) =>
+      operation === "comments"
+        ? Promise.reject(Object.assign(new Error("Unavailable"), { code: "network_error" }))
+        : request(operation),
+  });
+  await flush();
+  expect(document.getElementById("ryd-discussion-panel")).not.toBeNull();
+  expect(document.querySelector(".ryd-discussion-thread > .ryd-discussion-status").textContent).toBe(
+    "Unable to connect. Please try again.",
+  );
+});
+
+test("navigation removes outgoing content immediately and ignores its delayed response", async () => {
+  let resolve;
+  const call = jest.fn((operation) =>
+    operation === "comments"
+      ? new Promise((done) => {
+          resolve = done;
+        })
+      : request(operation),
+  );
+  feature = initDiscussion({ request: call });
+  await flush();
+  document.dispatchEvent(new Event("yt-navigate-start"));
+  expect(document.getElementById("ryd-discussion-panel")).toBeNull();
+  const commentsScope = call.mock.calls.find(([operation]) => operation === "comments")[2];
+  expect(commentsScope.videoId).toBe(VIDEO);
+  expect(call).toHaveBeenCalledWith("cancelScope", {}, commentsScope);
+  resolve({ items: [{ id: "late", text: "Old private draft" }] });
+  await flush();
+  window.history.replaceState({}, "", `/watch?v=${OTHER}`);
+  document.querySelector("ytd-watch-flexy").setAttribute("video-id", OTHER);
+  call.mockImplementation(request);
+  document.dispatchEvent(new Event("yt-navigate-finish"));
+  await flush();
+  expect(document.getElementById("ryd-discussion-panel").dataset.videoId).toBe(OTHER);
+  expect(document.body.textContent).not.toContain("Old private draft");
+});
+
+test("a logout event wins over an older initial session read", async () => {
+  let resolve;
+  feature = initDiscussion({
+    request: (operation) =>
+      operation === "session"
+        ? new Promise((done) => {
+            resolve = done;
+          })
+        : request(operation),
+  });
+  eventListener({
+    message: "ryd_discussion_event",
+    type: "session",
+    data: { authenticated: false, canPost: false, profile: null },
+  });
+  resolve({ authenticated: true, canPost: true, profile: { id: "old", nickname: "Previous" } });
+  await flush();
+  expect(document.querySelector("textarea[name='comment']")).toBeNull();
+  expect(document.body.textContent).not.toContain("Previous");
+});
+
+test("restoring a cached page recreates the panel with a fresh request scope", async () => {
+  const call = jest.fn(request);
+  feature = initDiscussion({ request: call });
+  await flush();
+  const previousScope = call.mock.calls.find(([operation]) => operation === "comments")[2];
+  window.dispatchEvent(new Event("pagehide"));
+  expect(document.getElementById("ryd-discussion-panel")).toBeNull();
+  expect(call).toHaveBeenCalledWith("cancelScope", {}, previousScope);
+  window.dispatchEvent(new Event("pageshow"));
+  await flush();
+  const reads = call.mock.calls.filter(([operation]) => operation === "comments");
+  expect(reads).toHaveLength(2);
+  expect(reads[1][2].videoId).toBe(VIDEO);
+  expect(reads[1][2].id).not.toBe(previousScope.id);
+  expect(document.querySelectorAll("#ryd-discussion-panel")).toHaveLength(1);
+});
+
+test("switching YouTube language refreshes the panel language", async () => {
+  feature = initDiscussion({ request });
+  await flush();
+  document.documentElement.lang = "ru";
+  await feature.refresh();
+  expect(document.querySelector(".ryd-discussion-title").textContent).toBe("Комментарии RYD");
+});
+
+test("an opened Shorts drawer survives a transiently hidden and replaced same-video container", async () => {
+  const oldReel = shortsFixture();
+  const call = jest.fn(request);
+  feature = initDiscussion({ request: call });
+  await flush();
+  document.getElementById("ryd-discussion-launcher").click();
+  const oldDrawer = document.getElementById("ryd-discussion-drawer");
+  const oldScope = call.mock.calls.find(([operation]) => operation === "comments")[2];
+  expect(oldDrawer.hidden).toBe(false);
+  oldReel.hidden = true;
+  await feature.refresh();
+  expect(document.getElementById("ryd-discussion-drawer")).toBeNull();
+  expect(call).toHaveBeenCalledWith("cancelScope", {}, oldScope);
+  shortsFixture();
+  await feature.refresh();
+  const nextDrawer = document.getElementById("ryd-discussion-drawer");
+  expect(nextDrawer).not.toBe(oldDrawer);
+  expect(nextDrawer.hidden).toBe(false);
+  expect(document.querySelector(".ryd-discussion-backdrop").hidden).toBe(false);
+  expect(document.getElementById("ryd-discussion-launcher").getAttribute("aria-expanded")).toBe("true");
+  expect(document.querySelectorAll("#ryd-discussion-drawer")).toHaveLength(1);
+  const nextScope = call.mock.calls.filter(([operation]) => operation === "comments").at(-1)[2];
+  expect(nextScope.videoId).toBe(VIDEO);
+  expect(nextScope.id).not.toBe(oldScope.id);
+});
+
+test("closing a Shorts drawer clears its intent before the native container is replaced", async () => {
+  shortsFixture();
+  feature = initDiscussion({ request });
+  await flush();
+  document.getElementById("ryd-discussion-launcher").click();
+  document.dispatchEvent(new KeyboardEvent("keydown", { key: "Escape", bubbles: true }));
+  shortsFixture();
+  await feature.refresh();
+  expect(document.getElementById("ryd-discussion-drawer").hidden).toBe(true);
+  expect(document.getElementById("ryd-discussion-launcher").getAttribute("aria-expanded")).toBe("false");
+});
+
+test.each(["navigation-event", "different-video"])(
+  "%s does not carry an opened Shorts drawer into the next panel",
+  async (change) => {
+    shortsFixture();
+    feature = initDiscussion({ request });
+    await flush();
+    document.getElementById("ryd-discussion-launcher").click();
+    if (change === "navigation-event") document.dispatchEvent(new Event("yt-navigate-start"));
+    shortsFixture(change === "different-video" ? OTHER : VIDEO);
+    if (change === "navigation-event") document.dispatchEvent(new Event("yt-navigate-finish"));
+    else await feature.refresh();
+    await flush();
+    expect(document.getElementById("ryd-discussion-drawer").hidden).toBe(true);
+  },
+);
+
+test("remembered Shorts open intent cannot retain an ineligible panel", async () => {
+  const reel = shortsFixture();
+  feature = initDiscussion({ request });
+  await flush();
+  document.getElementById("ryd-discussion-launcher").click();
+  reel.setAttribute("made-for-kids", "true");
+  await feature.refresh();
+  expect(document.getElementById("ryd-discussion-drawer")).toBeNull();
+  expect(document.getElementById("ryd-discussion-launcher")).toBeNull();
+  expect(document.querySelector(".ryd-discussion-backdrop")).toBeNull();
+});
+
+test("a hash target focuses a reply in an existing panel and switches from inbox without stealing focus again", async () => {
+  const call = jest.fn(linkRequest);
+  feature = initDiscussion({ request: call });
+  await flush();
+  const original = document.getElementById("ryd-discussion-panel");
+  original.querySelector("[data-action=inbox]").click();
+  window.history.replaceState({}, "", `/watch?v=${VIDEO}#rydComment=${REPLY_COMMENT}`);
+  window.dispatchEvent(new Event("hashchange"));
+  await flush();
+  expect(document.getElementById("ryd-discussion-panel")).toBe(original);
+  expect(original.querySelector(".ryd-discussion-inbox").hidden).toBe(true);
+  expect(document.activeElement.dataset.commentId).toBe(REPLY_COMMENT);
+  const before = call.mock.calls.filter(([operation]) => operation === "comment").length;
+  const tab = original.querySelector("[data-action=discussion]");
+  tab.focus();
+  await feature.refresh();
+  expect(document.activeElement).toBe(tab);
+  expect(call.mock.calls.filter(([operation]) => operation === "comment")).toHaveLength(before);
+  window.history.replaceState({}, "", `/watch?v=${VIDEO}#rydComment=${ROOT_COMMENT}`);
+  window.dispatchEvent(new Event("popstate"));
+  await flush();
+  expect(document.activeElement.dataset.commentId).toBe(ROOT_COMMENT);
+});
+
+test.each(["watch", "shorts"])(
+  "a same-video %s toast click focuses directly before native navigation",
+  async (surface) => {
+    if (surface === "shorts") shortsFixture();
+    const call = jest.fn(linkRequest);
+    feature = initDiscussion({ request: call });
+    await flush();
+    const anchor = notificationAnchor();
+    const click = new MouseEvent("click", { bubbles: true, cancelable: true, button: 0 });
+    anchor.dispatchEvent(click);
+    expect(click.defaultPrevented).toBe(true);
+    expect(location.hash).toBe(`#rydComment=${REPLY_COMMENT}`);
+    expect(location.pathname).toBe(surface === "shorts" ? `/shorts/${VIDEO}` : "/watch");
+    await flush();
+    expect(document.activeElement.dataset.commentId).toBe(REPLY_COMMENT);
+    expect(call).toHaveBeenCalledWith("readNotifications", { ids: [ROOT_COMMENT] });
+    if (surface === "shorts") expect(document.getElementById("ryd-discussion-drawer").hidden).toBe(false);
+  },
+);
+
+test.each([
+  { ctrlKey: true },
+  { metaKey: true },
+  { shiftKey: true },
+  { altKey: true },
+  { button: 1 },
+  { target: "_blank" },
+  { videoId: OTHER },
+])("notification links preserve modified clicks and separate destinations: %j", async (options) => {
+  feature = initDiscussion({ request: linkRequest });
+  await flush();
+  const anchor = notificationAnchor(options);
+  let preventedByFeature;
+  anchor.addEventListener("click", (event) => {
+    preventedByFeature = event.defaultPrevented;
+    event.preventDefault();
+  });
+  anchor.dispatchEvent(new MouseEvent("click", { bubbles: true, cancelable: true, button: 0, ...options }));
+  expect(preventedByFeature).toBe(false);
+  expect(location.hash).toBe("");
+});
+
+test("a new page opened with a fragment focuses its target after initial panel hydration", async () => {
+  window.history.replaceState({}, "", `/watch?v=${VIDEO}#rydComment=${REPLY_COMMENT}`);
+  feature = initDiscussion({ request: linkRequest });
+  await flush();
+  expect(document.activeElement.dataset.commentId).toBe(REPLY_COMMENT);
+});
diff --git a/Extensions/combined/src/discussion/localize.js b/Extensions/combined/src/discussion/localize.js
new file mode 100644
index 0000000..393d40e
--- /dev/null
+++ b/Extensions/combined/src/discussion/localize.js
@@ -0,0 +1,44 @@
+import english from "../../_locales/en/messages.json";
+import russian from "../../_locales/ru/messages.json";
+
+export function discussionLanguage(language = document.documentElement.lang || navigator.language) {
+  return /^ru(?:-|$)/i.test(language || "") ? "ru" : "en";
+}
+
+export function discussionText(key, substitutions = [], language) {
+  const name = `discussion_${key}`;
+  const catalog = discussionLanguage(language) === "ru" ? russian : english;
+  const text = catalog[name]?.message || english[name]?.message || key;
+  return text.replace(/\$(\d+)/g, (_, number) => String(substitutions[Number(number) - 1] ?? ""));
+}
+
+export function discussionError(error) {
+  const keys = {
+    nickname_required: "nicknameRequired",
+    nickname_taken: "nicknameTaken",
+    invalid_nickname: "nicknameInvalid",
+    membership_tier_insufficient: "tierRequired",
+    membership_inactive: "tierRequired",
+    invalid_session: "signInRequired",
+    session_upgrade_required: "signInRequired",
+    unauthorized: "signInRequired",
+    comments_not_allowed: "unavailable",
+    comments_disabled_required: "unavailable",
+    made_for_kids: "unavailable",
+    video_not_eligible: "unavailable",
+    comment_not_found: "commentUnavailable",
+    not_found: "commentUnavailable",
+    rate_limited: "rateLimited",
+    conflict: "conflict",
+    forbidden: "forbidden",
+  };
+  const statusKey =
+    error?.status === 401
+      ? "signInRequired"
+      : error?.status === 403
+        ? "forbidden"
+        : error?.status === 429
+          ? "rateLimited"
+          : "error";
+  return discussionText(keys[error?.code] || statusKey);
+}
diff --git a/Extensions/combined/src/discussion/panel.js b/Extensions/combined/src/discussion/panel.js
new file mode 100644
index 0000000..0f6b9c2
--- /dev/null
+++ b/Extensions/combined/src/discussion/panel.js
@@ -0,0 +1,700 @@
+import { requestDiscussion } from "./client";
+import { discussionText as t, discussionError, discussionLanguage } from "./localize";
+import { element, button, statusNode, shortDate, thumbIcon, isDiscussionCommentId } from "./dom";
+import { createDiscussionInbox } from "./inbox";
+
+const SIGNED_OUT = { authenticated: false, canPost: false, isModerator: false, profile: null };
+
+export function createDiscussionPanel({
+  videoId,
+  surface = "watch",
+  session = SIGNED_OUT,
+  capabilities = {},
+  request = requestDiscussion,
+  onClose,
+} = {}) {
+  const maxLength = capabilities.maxCommentLength || 2000;
+  const root = element("section", `ryd-discussion ryd-discussion-${surface}`);
+  root.id = surface === "shorts" ? "ryd-discussion-drawer" : "ryd-discussion-panel";
+  root.dataset.videoId = videoId;
+  root.setAttribute("aria-label", t("title"));
+  if (surface === "shorts") {
+    root.setAttribute("role", "dialog");
+    root.setAttribute("aria-modal", "true");
+    root.tabIndex = -1;
+  }
+  const header = element("header", "ryd-discussion-header");
+  const brand = element("div", "ryd-discussion-brand");
+  brand.append(element("span", "ryd-discussion-logo", "RYD"), element("h2", "ryd-discussion-title", t("title")));
+  const headerButtons = element("div", "ryd-discussion-header-actions");
+  const inboxButton = button(t("notifications"), () => showTab("inbox"));
+  const moderationButton = button(t("moderation"), () => showTab("moderation"));
+  const discussionButton = button(t("discussionTab"), () => showTab("discussion"));
+  inboxButton.dataset.action = "inbox";
+  moderationButton.dataset.action = "moderation";
+  discussionButton.dataset.action = "discussion";
+  headerButtons.append(discussionButton, inboxButton, moderationButton);
+  if (onClose) {
+    const close = button("×", onClose, "ryd-discussion-close");
+    close.setAttribute("aria-label", t("close"));
+    headerButtons.append(close);
+  }
+  header.append(brand, headerButtons);
+  const intro = element("p", "ryd-discussion-description", t("subtitle"));
+  const independent = element("p", "ryd-discussion-independent", t("independent"));
+  const body = element("div", "ryd-discussion-body");
+  const discussion = element("div", "ryd-discussion-thread");
+  const composer = element("div", "ryd-discussion-composer");
+  const toolbar = element("div", "ryd-discussion-toolbar");
+  const sort = element("select", "ryd-discussion-select");
+  sort.setAttribute("aria-label", t("sort"));
+  for (const value of ["top", "new"]) {
+    const option = element("option", "", t(value));
+    option.value = value;
+    sort.append(option);
+  }
+  sort.addEventListener("change", () => load());
+  const refresh = button(t("refresh"), () => load());
+  toolbar.append(sort, refresh);
+  const status = statusNode();
+  const list = element("div", "ryd-discussion-comments");
+  const more = button(t("more"), () => load(true), "ryd-discussion-button ryd-discussion-more");
+  more.hidden = true;
+  discussion.append(composer, toolbar, status, list, more);
+  const inbox = createDiscussionInbox({ request, authenticated: session.authenticated });
+  const moderation = element("div", "ryd-discussion-moderation");
+  inbox.node.hidden = true;
+  moderation.hidden = true;
+  body.append(discussion, inbox.node, moderation);
+  root.append(header, intro, independent, body);
+  let disposed = false;
+  let accountGeneration = 0;
+  let sequence = 0;
+  let items = [];
+  let cursor = null;
+  let activeTab = "discussion";
+  const drafts = new Map();
+  const postingIds = new Map();
+  const rootReplyHandlers = new Map();
+  let moderationSequence = 0;
+  let reportCursor = null;
+  let reportStatus = "open";
+  let reports = [];
+  let highlightedId = null;
+  let focusSequence = 0;
+
+  function current() {
+    return !disposed;
+  }
+  function setError(error) {
+    if (current()) status.textContent = discussionError(error);
+  }
+
+  function showTab(tab, reload = true) {
+    if (tab === "moderation" && !session.isModerator) return;
+    if (tab === "inbox" && !session.authenticated) return;
+    const previousTab = activeTab;
+    activeTab = tab;
+    discussion.hidden = tab !== "discussion";
+    inbox.node.hidden = tab !== "inbox";
+    moderation.hidden = tab !== "moderation";
+    discussionButton.setAttribute("aria-pressed", String(tab === "discussion"));
+    inboxButton.setAttribute("aria-pressed", String(tab === "inbox"));
+    moderationButton.setAttribute("aria-pressed", String(tab === "moderation"));
+    if (tab === "inbox") inbox.load();
+    if (tab === "moderation") loadReports();
+    if (reload && tab === "discussion" && previousTab === "moderation") load();
+  }
+
+  function renderSession() {
+    inboxButton.hidden = !session.authenticated;
+    moderationButton.hidden = !session.isModerator;
+    discussionButton.hidden = !session.authenticated;
+    if ((activeTab === "inbox" && !session.authenticated) || (activeTab === "moderation" && !session.isModerator))
+      showTab("discussion");
+    composer.replaceChildren();
+    if (!session.canPost || session.profile?.suspended) {
+      composer.append(element("p", "ryd-discussion-gate", t("gate")));
+      const join = element("a", "ryd-discussion-link", t("join"));
+      join.href = "https://www.patreon.com/returnyoutubedislike/membership";
+      join.target = "_blank";
+      join.rel = "noopener noreferrer";
+      composer.append(join);
+      if (!session.authenticated) composer.append(element("p", "ryd-discussion-meta", t("signInRequired")));
+    } else if (!session.profile?.nickname) {
+      composer.append(nicknameForm());
+    } else {
+      const account = element("div", "ryd-discussion-account");
+      account.append(
+        element("span", "ryd-discussion-meta", t("as", [session.profile.nickname])),
+        button(t("nicknameChange"), () => {
+          composer.replaceChildren(nicknameForm(true));
+        }),
+      );
+      composer.append(account, commentForm());
+    }
+    renderComments();
+  }
+
+  function nicknameForm(allowCancel = false) {
+    const form = element("form", "ryd-discussion-form");
+    const label = element("label", "ryd-discussion-label", t("nicknameLabel"));
+    const input = element("input", "ryd-discussion-input");
+    input.name = "nickname";
+    input.value = session.profile?.nickname || "";
+    input.required = true;
+    input.minLength = capabilities.minNicknameLength || 3;
+    input.maxLength = capabilities.maxNicknameLength || 32;
+    input.autocomplete = "nickname";
+    label.append(input);
+    const message = statusNode();
+    const actions = element("div", "ryd-discussion-form-actions");
+    const submit = button(t("nicknameSave"), null, "ryd-discussion-button ryd-discussion-primary");
+    submit.type = "submit";
+    actions.append(submit);
+    if (allowCancel) actions.append(button(t("cancel"), renderSession));
+    form.append(
+      element("p", "ryd-discussion-description", t("nicknameRequired")),
+      label,
+      element("p", "ryd-discussion-meta", t("nicknameHint")),
+      message,
+      actions,
+    );
+    form.addEventListener("submit", async (event) => {
+      event.preventDefault();
+      if (submit.disabled) return;
+      const nickname = input.value.trim().normalize("NFKC");
+      if (
+        nickname.length < input.minLength ||
+        nickname.length > input.maxLength ||
+        !/^[\p{L}\p{N} ._-]+$/u.test(nickname) ||
+        !/[\p{L}\p{N}]/u.test(nickname)
+      ) {
+        message.textContent = t("nicknameInvalid");
+        return;
+      }
+      submit.disabled = true;
+      message.textContent = t("saving");
+      const accountSnapshot = accountGeneration;
+      try {
+        const result = await request("profile", { nickname });
+        if (!current() || accountSnapshot !== accountGeneration) return;
+        session = result;
+        renderSession();
+      } catch (error) {
+        if (current()) message.textContent = discussionError(error);
+      } finally {
+        submit.disabled = false;
+      }
+    });
+    return form;
+  }
+
+  function commentForm({ parentId = null, replyToId = null, comment = null, onCancel, onSaved } = {}) {
+    const key = comment ? `edit:${comment.id}` : `reply:${replyToId || "root"}`;
+    const form = element("form", "ryd-discussion-form");
+    const label = element("label", "ryd-discussion-label");
+    label.append(element("span", "ryd-discussion-sr-only", t(comment ? "edit" : replyToId ? "reply" : "comment")));
+    const input = element("textarea", "ryd-discussion-textarea");
+    input.name = "comment";
+    input.placeholder = t("placeholder");
+    input.rows = 3;
+    input.maxLength = maxLength;
+    input.required = true;
+    input.value = drafts.get(key) ?? comment?.text ?? "";
+    label.append(input);
+    const footer = element("div", "ryd-discussion-form-actions");
+    const counter = element("span", "ryd-discussion-counter");
+    const submit = button(
+      t(comment ? "save" : replyToId ? "postReply" : "post"),
+      null,
+      "ryd-discussion-button ryd-discussion-primary",
+    );
+    submit.type = "submit";
+    submit.dataset.action = comment ? "save" : "post";
+    const update = () => {
+      drafts.set(key, input.value);
+      counter.textContent = t("characters", [input.value.length, maxLength]);
+      submit.disabled = !input.value.trim() || input.value.length > maxLength;
+      postingIds.delete(key);
+    };
+    input.addEventListener("input", update);
+    input.addEventListener("keydown", (event) => {
+      if ((event.ctrlKey || event.metaKey) && event.key === "Enter") {
+        event.preventDefault();
+        form.requestSubmit();
+      }
+    });
+    counter.textContent = t("characters", [input.value.length, maxLength]);
+    submit.disabled = !input.value.trim();
+    footer.append(counter);
+    if (onCancel) footer.append(button(t("cancel"), onCancel));
+    footer.append(submit);
+    const message = statusNode();
+    form.append(label, message, footer);
+    form.addEventListener("submit", async (event) => {
+      event.preventDefault();
+      if (submit.disabled) return;
+      const text = input.value.trim();
+      if (!text || text.length > maxLength) return;
+      submit.disabled = true;
+      input.disabled = true;
+      message.textContent = t("saving");
+      const requestId = postingIds.get(key) || globalThis.crypto.randomUUID();
+      postingIds.set(key, requestId);
+      try {
+        const payload = comment
+          ? { id: comment.id, text }
+          : { videoId, text, requestId, ...(parentId ? { parentId, replyToId } : {}) };
+        const result = await request(comment ? "editComment" : "createComment", payload);
+        if (!current()) return;
+        drafts.delete(key);
+        postingIds.delete(key);
+        if (onSaved) onSaved(result);
+        else {
+          input.value = "";
+          update();
+          message.textContent = "";
+          await load();
+        }
+      } catch (error) {
+        if (current()) message.textContent = discussionError(error);
+      } finally {
+        if (current()) {
+          input.disabled = false;
+          submit.disabled = !input.value.trim();
+        }
+      }
+    });
+    return form;
+  }
+
+  function commentRow(comment, rootId = comment.parentId || comment.id) {
+    const row = element("article", `ryd-discussion-comment${comment.parentId ? " ryd-discussion-reply" : ""}`);
+    row.dataset.commentId = comment.id;
+    if (comment.id === highlightedId) row.classList.add("is-highlighted");
+    const heading = element("div", "ryd-discussion-comment-heading");
+    const initial = (comment.author?.nickname || "RYD").slice(0, 1).toUpperCase();
+    heading.append(
+      element("span", "ryd-discussion-avatar", initial),
+      element("strong", "ryd-discussion-author", comment.author?.nickname || t("deleted")),
+    );
+    const date = element("time", "ryd-discussion-meta", shortDate(comment.createdAt, discussionLanguage()));
+    date.dateTime = comment.createdAt;
+    heading.append(date);
+    if (comment.editedAt) heading.append(element("span", "ryd-discussion-meta", t("edited")));
+    const text = element(
+      "p",
+      "ryd-discussion-comment-text",
+      comment.deleted || comment.hidden ? t("deleted") : comment.text,
+    );
+    const actions = element("div", "ryd-discussion-comment-actions");
+    const controls = element("div", "ryd-discussion-inline-editor");
+    const replies = element("div", "ryd-discussion-replies");
+    row.append(heading, text, actions, controls, replies);
+    const alive = () => current() && row.isConnected;
+    if (!comment.deleted && !comment.hidden) {
+      for (const value of [1, -1]) {
+        const reaction = button(
+          "",
+          async () => {
+            if (reaction.disabled) return;
+            const buttons = [...actions.querySelectorAll("[data-reaction]")];
+            buttons.forEach((item) => {
+              item.disabled = true;
+            });
+            try {
+              const result = await request("react", {
+                id: comment.id,
+                value: comment.myReaction === value ? 0 : value,
+              });
+              if (!alive()) return;
+              Object.assign(comment, result);
+              updateReactions();
+            } catch (error) {
+              setError(error);
+            } finally {
+              buttons.forEach((item) => {
+                item.disabled = false;
+              });
+            }
+          },
+          "ryd-discussion-button ryd-discussion-reaction",
+        );
+        reaction.dataset.reaction = String(value);
+        actions.append(reaction);
+      }
+      function updateReactions() {
+        for (const reaction of actions.querySelectorAll("[data-reaction]")) {
+          const liked = reaction.dataset.reaction === "1";
+          const count = liked ? comment.likes || 0 : comment.dislikes || 0;
+          reaction.replaceChildren(thumbIcon(!liked), element("span", "", count.toLocaleString(discussionLanguage())));
+          reaction.setAttribute("aria-label", `${t(liked ? "like" : "dislike")} (${count})`);
+          reaction.setAttribute("aria-pressed", String(comment.myReaction === (liked ? 1 : -1)));
+        }
+      }
+      updateReactions();
+      const reply = button(t("reply"), () => {
+        controls.replaceChildren();
+        if (!session.canPost) {
+          controls.append(element("p", "ryd-discussion-gate", t("tierRequired")));
+          return;
+        }
+        if (!session.profile?.nickname) {
+          controls.append(nicknameForm());
+          return;
+        }
+        controls.append(
+          commentForm({
+            parentId: rootId,
+            replyToId: comment.id,
+            onCancel: () => controls.replaceChildren(),
+            onSaved: (created) => {
+              controls.replaceChildren();
+              rootReplyHandlers.get(rootId)?.(created);
+            },
+          }),
+        );
+        controls.querySelector("textarea")?.focus();
+      });
+      reply.dataset.action = "reply";
+      actions.append(reply);
+      if (session.authenticated && comment.author?.id === session.profile?.id) {
+        if (comment.canEdit) {
+          const edit = button(t("edit"), () => {
+            controls.replaceChildren(
+              commentForm({
+                comment,
+                onCancel: () => controls.replaceChildren(),
+                onSaved: (updated) => {
+                  Object.assign(comment, updated);
+                  row.replaceWith(commentRow(comment, rootId));
+                },
+              }),
+            );
+            controls.querySelector("textarea")?.focus();
+          });
+          edit.dataset.action = "edit";
+          actions.append(edit);
+        }
+        if (comment.canDelete) {
+          const remove = button(t("delete"), () => {
+            const prompt = element("div", "ryd-discussion-confirm");
+            prompt.append(
+              element("span", "", t("deleteConfirm")),
+              button(t("cancel"), () => controls.replaceChildren()),
+            );
+            const confirm = button(
+              t("delete"),
+              async () => {
+                confirm.disabled = true;
+                try {
+                  const updated = await request("deleteComment", { id: comment.id });
+                  if (alive()) {
+                    Object.assign(comment, updated);
+                    row.replaceWith(commentRow(comment, rootId));
+                  }
+                } catch (error) {
+                  setError(error);
+                  confirm.disabled = false;
+                }
+              },
+              "ryd-discussion-button ryd-discussion-danger",
+            );
+            confirm.dataset.action = "confirm-delete";
+            prompt.append(confirm);
+            controls.replaceChildren(prompt);
+          });
+          remove.dataset.action = "delete";
+          actions.append(remove);
+        }
+      }
+      if (session.authenticated) {
+        const report = button(t("report"), () => showReport(comment, controls));
+        report.dataset.action = "report";
+        actions.append(report);
+      }
+    }
+    let repliesCursor = null;
+    let replyItems = [];
+    let replySequence = 0;
+    let replyLoading = false;
+    let repliesLoaded = false;
+    const moreReplies = button(t("more"), () => loadReplies(true));
+    const showReplies = button(t("loadReplies", [comment.replyCount || 0]), () => loadReplies());
+    showReplies.dataset.action = "load-replies";
+    showReplies.hidden = Boolean(comment.parentId) || !comment.replyCount;
+    actions.append(showReplies);
+    function renderReplies() {
+      const timestamp = (value) =>
+        String(value).replace(/(?:\.(\d+))?Z$/, (_, fraction = "") => `.${fraction.padEnd(9, "0")}Z`);
+      replyItems = [...new Map(replyItems.map((item) => [item.id, item])).values()].sort(
+        (a, b) => timestamp(a.createdAt).localeCompare(timestamp(b.createdAt)) || a.id.localeCompare(b.id),
+      );
+      comment.replyCount = Math.max(comment.replyCount || 0, replyItems.length);
+      replies.replaceChildren(...replyItems.map((item) => commentRow(item, rootId)));
+      if (repliesCursor) replies.append(moreReplies);
+    }
+    function addReply(created) {
+      if (!alive()) return;
+      if (!replyItems.some((item) => item.id === created.id)) comment.replyCount = (comment.replyCount || 0) + 1;
+      replyItems.push(created);
+      renderReplies();
+      showReplies.textContent = t("loadReplies", [comment.replyCount]);
+      showReplies.hidden = repliesLoaded;
+      if (!repliesLoaded) loadReplies();
+    }
+    async function loadReplies(append = false) {
+      if (replyLoading) return;
+      replyLoading = true;
+      showReplies.disabled = true;
+      const currentReply = ++replySequence;
+      try {
+        const result = await request("replies", {
+          rootId,
+          ...(append && repliesCursor ? { cursor: repliesCursor } : {}),
+        });
+        if (!alive() || currentReply !== replySequence) return;
+        replyItems = [...replyItems, ...(result.items || [])];
+        repliesCursor = result.nextCursor;
+        repliesLoaded = true;
+        renderReplies();
+        showReplies.hidden = true;
+      } catch (error) {
+        setError(error);
+      } finally {
+        showReplies.disabled = false;
+        replyLoading = false;
+      }
+    }
+    if (!comment.parentId) rootReplyHandlers.set(comment.id, addReply);
+    return row;
+  }
+
+  function showReport(comment, host) {
+    const form = element("form", "ryd-discussion-form");
+    const label = element("label", "ryd-discussion-label", t("reportReason"));
+    const reason = element("select", "ryd-discussion-select");
+    for (const [value, key] of [
+      ["spam", "reportSpam"],
+      ["abuse", "reportAbuse"],
+      ["other", "reportOther"],
+    ]) {
+      const option = element("option", "", t(key));
+      option.value = value;
+      reason.append(option);
+    }
+    label.append(reason);
+    const detailsLabel = element("label", "ryd-discussion-label", t("reportDetails"));
+    const details = element("textarea", "ryd-discussion-textarea");
+    details.maxLength = 400;
+    details.rows = 2;
+    detailsLabel.append(details);
+    const message = statusNode();
+    const submit = button(t("reportSend"), null, "ryd-discussion-button ryd-discussion-primary");
+    submit.type = "submit";
+    submit.dataset.action = "send-report";
+    const actions = element("div", "ryd-discussion-form-actions");
+    actions.append(
+      button(t("cancel"), () => host.replaceChildren()),
+      submit,
+    );
+    form.append(element("h4", "ryd-discussion-subtitle", t("reportTitle")), label, detailsLabel, message, actions);
+    form.addEventListener("submit", async (event) => {
+      event.preventDefault();
+      if (submit.disabled) return;
+      submit.disabled = true;
+      try {
+        await request("report", {
+          id: comment.id,
+          reason: `${reason.value}${details.value.trim() ? `: ${details.value.trim()}` : ""}`,
+        });
+        if (current()) host.replaceChildren(element("p", "ryd-discussion-status", t("reportDone")));
+      } catch (error) {
+        message.textContent = discussionError(error);
+        submit.disabled = false;
+      }
+    });
+    host.replaceChildren(form);
+  }
+
+  function renderComments() {
+    rootReplyHandlers.clear();
+    list.replaceChildren(...items.map((item) => commentRow(item)));
+  }
+
+  async function load(append = false) {
+    if (!current()) return;
+    const currentSequence = ++sequence;
+    status.textContent = t("loading");
+    refresh.disabled = true;
+    more.disabled = true;
+    try {
+      const result = await request("comments", { videoId, sort: sort.value, ...(append && cursor ? { cursor } : {}) });
+      if (!current() || currentSequence !== sequence) return;
+      items = append ? [...items, ...(result.items || [])] : result.items || [];
+      items = [...new Map(items.map((item) => [item.id, item])).values()];
+      cursor = result.nextCursor;
+      renderComments();
+      status.textContent = items.length ? "" : t("empty");
+      more.hidden = !cursor;
+    } catch (error) {
+      if (current() && currentSequence === sequence) setError(error);
+    } finally {
+      if (current() && currentSequence === sequence) {
+        refresh.disabled = false;
+        more.disabled = false;
+      }
+    }
+  }
+
+  async function loadReports(append = false) {
+    if (!current() || !session.isModerator) return;
+    const currentSequence = ++moderationSequence;
+    moderation.replaceChildren(element("p", "ryd-discussion-status", t("loading")));
+    try {
+      const result = await request("reports", {
+        status: reportStatus,
+        ...(append && reportCursor ? { cursor: reportCursor } : {}),
+      });
+      if (!current() || currentSequence !== moderationSequence || !session.isModerator) return;
+      reports = append ? [...reports, ...(result.items || [])] : result.items || [];
+      reportCursor = result.nextCursor;
+      const reportToolbar = element("div", "ryd-discussion-toolbar");
+      const reportFilter = element("select", "ryd-discussion-select");
+      reportFilter.dataset.action = "report-status";
+      reportFilter.setAttribute("aria-label", t("reportStatus"));
+      for (const [value, label] of [
+        ["open", "openReports"],
+        ["resolved", "resolvedReports"],
+      ]) {
+        const option = element("option", "", t(label));
+        option.value = value;
+        reportFilter.append(option);
+      }
+      reportFilter.value = reportStatus;
+      reportFilter.addEventListener("change", () => {
+        reportStatus = reportFilter.value;
+        reportCursor = null;
+        loadReports();
+      });
+      reportToolbar.append(element("h3", "ryd-discussion-subtitle", t("moderation")), reportFilter);
+      moderation.replaceChildren(reportToolbar);
+      if (!reports.length) moderation.append(element("p", "ryd-discussion-status", t("queueEmpty")));
+      for (const report of reports) {
+        const row = element("article", "ryd-discussion-report");
+        row.dataset.reportId = report.id;
+        row.append(
+          element("strong", "ryd-discussion-author", report.comment?.author?.nickname || t("deleted")),
+          element("p", "ryd-discussion-comment-text", report.comment?.text || t("deleted")),
+          element("p", "ryd-discussion-report-reason", report.reason),
+        );
+        const reasonLabel = element("label", "ryd-discussion-label", t("moderationReason"));
+        const reason = element("input", "ryd-discussion-input");
+        reason.maxLength = 300;
+        reasonLabel.append(reason);
+        row.append(reasonLabel);
+        const actions = element("div", "ryd-discussion-comment-actions");
+        const feedback = statusNode();
+        const addAction = (key, operation, payload) => {
+          const action = button(t(key), async () => {
+            const buttons = [...actions.querySelectorAll("button")];
+            buttons.forEach((item) => {
+              item.disabled = true;
+            });
+            try {
+              await request(operation, { ...payload, ...(reason.value.trim() ? { reason: reason.value.trim() } : {}) });
+              if (current()) await loadReports();
+            } catch (error) {
+              feedback.textContent = discussionError(error);
+              buttons.forEach((item) => {
+                item.disabled = false;
+              });
+            }
+          });
+          action.dataset.action = key;
+          actions.append(action);
+        };
+        if (reportStatus === "open") addAction("dismiss", "dismissReport", { id: report.id });
+        addAction(report.comment?.hidden ? "restore" : "hide", "moderateComment", {
+          id: report.comment.id,
+          hidden: !report.comment.hidden,
+        });
+        if (report.comment.author)
+          addAction(report.authorSuspended ? "unban" : "ban", "suspendProfile", {
+            id: report.comment.author.id,
+            suspended: !report.authorSuspended,
+          });
+        row.append(actions, feedback);
+        moderation.append(row);
+      }
+      if (reportCursor) moderation.append(button(t("more"), () => loadReports(true)));
+    } catch (error) {
+      if (current() && currentSequence === moderationSequence)
+        moderation.replaceChildren(
+          element("p", "ryd-discussion-status", discussionError(error)),
+          button(t("retry"), () => loadReports()),
+        );
+    }
+  }
+
+  async function focusComment(id) {
+    if (!isDiscussionCommentId(id)) return;
+    const focus = ++focusSequence;
+    const account = accountGeneration;
+    const stillCurrent = () => current() && focus === focusSequence && account === accountGeneration;
+    try {
+      const target = await request("comment", { id });
+      if (!stillCurrent() || target.videoId !== videoId) return;
+      highlightedId = id;
+      const threadRoot = target.parentId ? await request("comment", { id: target.parentId }) : target;
+      if (!stillCurrent() || threadRoot.videoId !== videoId) return;
+      showTab("discussion", false);
+      if (!items.some((item) => item.id === threadRoot.id)) items.unshift(threadRoot);
+      renderComments();
+      const row = [...list.querySelectorAll("[data-comment-id]")].find(
+        (item) => item.dataset.commentId === threadRoot.id,
+      );
+      if (target.parentId) row.querySelector(".ryd-discussion-replies").append(commentRow(target, threadRoot.id));
+      const focused = [...list.querySelectorAll("[data-comment-id]")].find((item) => item.dataset.commentId === id);
+      focused?.scrollIntoView?.({ block: "center", behavior: "smooth" });
+      if (focused) {
+        focused.tabIndex = -1;
+        focused.focus({ preventScroll: true });
+      }
+    } catch (error) {
+      if (stillCurrent()) setError(error);
+    }
+  }
+
+  renderSession();
+  showTab("discussion");
+  return {
+    root,
+    load,
+    focusComment,
+    setSession(next) {
+      const previousIdentity = session.authenticated ? session.profile?.id || "authenticated" : "anonymous";
+      const nextIdentity = next?.authenticated ? next.profile?.id || "authenticated" : "anonymous";
+      accountGeneration++;
+      moderationSequence++;
+      session = next || SIGNED_OUT;
+      inbox.setSession(session);
+      renderSession();
+      if (previousIdentity !== nextIdentity) load();
+    },
+    setInbox(value) {
+      inbox.update(value, { live: true });
+      inboxButton.textContent = `${t("notifications")}${value?.unreadCount ? ` (${value.unreadCount})` : ""}`;
+    },
+    destroy() {
+      disposed = true;
+      sequence++;
+      moderationSequence++;
+      drafts.clear();
+      postingIds.clear();
+      inbox.destroy();
+      root.remove();
+    },
+  };
+}
diff --git a/Extensions/combined/src/discussion/panel.spec.js b/Extensions/combined/src/discussion/panel.spec.js
new file mode 100644
index 0000000..05ce6a0
--- /dev/null
+++ b/Extensions/combined/src/discussion/panel.spec.js
@@ -0,0 +1,433 @@
+/** @jest-environment jsdom */
+
+import { createDiscussionPanel } from "./panel";
+import { discussionText } from "./localize";
+
+const VIDEO = "abcdefghijk";
+const ROOT = "11111111-1111-1111-1111-111111111111";
+const REPLY = "22222222-2222-2222-2222-222222222222";
+const PROFILE = "33333333-3333-3333-3333-333333333333";
+const session = {
+  authenticated: true,
+  canPost: true,
+  isModerator: false,
+  profile: { id: PROFILE, nickname: "Writer" },
+};
+const flush = async () => {
+  for (let i = 0; i < 15; i++) await Promise.resolve();
+};
+let panel;
+let request;
+
+function comment(overrides = {}) {
+  return {
+    id: ROOT,
+    videoId: VIDEO,
+    parentId: null,
+    replyToId: null,
+    author: { id: PROFILE, nickname: "Writer" },
+    text: "First comment",
+    createdAt: "2026-09-01T12:00:00Z",
+    editedAt: null,
+    deleted: false,
+    hidden: false,
+    likes: 2,
+    dislikes: 1,
+    myReaction: 0,
+    replyCount: 0,
+    canEdit: true,
+    canDelete: true,
+    ...overrides,
+  };
+}
+
+async function mount(options = {}, comments = [comment()]) {
+  request = jest.fn(async (operation) =>
+    operation === "comments" ? { items: comments, nextCursor: null } : { items: [], nextCursor: null },
+  );
+  panel = createDiscussionPanel({ videoId: VIDEO, request, ...options });
+  document.body.append(panel.root);
+  await panel.load();
+  return panel.root;
+}
+
+function submit(form, text) {
+  const input = form.querySelector("textarea");
+  input.value = text;
+  input.dispatchEvent(new Event("input", { bubbles: true }));
+  form.dispatchEvent(new Event("submit", { bubbles: true, cancelable: true }));
+}
+
+beforeEach(() => {
+  document.body.replaceChildren();
+  document.documentElement.lang = "en";
+  Object.defineProperty(globalThis.crypto, "randomUUID", {
+    configurable: true,
+    value: () => "44444444-4444-4444-4444-444444444444",
+  });
+});
+afterEach(() => panel?.destroy());
+
+test("an older comment deep-link response cannot replace the user's newer focused target", async () => {
+  const root = await mount({ session });
+  let resolveReply;
+  request.mockImplementation((operation, payload) => {
+    if (operation === "comment" && payload.id === REPLY)
+      return new Promise((resolve) => {
+        resolveReply = resolve;
+      });
+    if (operation === "comment") return Promise.resolve(comment());
+    return Promise.resolve({ items: [], nextCursor: null });
+  });
+  const oldFocus = panel.focusComment(REPLY);
+  await panel.focusComment(ROOT);
+  resolveReply(comment({ id: REPLY, parentId: ROOT, text: "Older linked reply" }));
+  await oldFocus;
+  expect(document.activeElement.dataset.commentId).toBe(ROOT);
+  expect(root.querySelector(`[data-comment-id="${REPLY}"]`)).toBeNull();
+});
+
+test("signed-out users can react without seeing author or moderator controls", async () => {
+  const root = await mount();
+  expect(root.querySelector("textarea")).toBeNull();
+  expect(root.querySelector("[data-action='edit']")).toBeNull();
+  expect(root.querySelector("[data-action='moderation']").hidden).toBe(true);
+  request.mockResolvedValueOnce({ commentId: ROOT, likes: 3, dislikes: 1, myReaction: 1 });
+  root.querySelector("[data-reaction='1']").click();
+  await flush();
+  expect(request).toHaveBeenLastCalledWith("react", { id: ROOT, value: 1 });
+  expect(root.querySelector("[data-reaction='1']").getAttribute("aria-pressed")).toBe("true");
+  expect(root.querySelector("[data-reaction='1']").textContent).toBe("3");
+  request.mockResolvedValueOnce({ commentId: ROOT, likes: 2, dislikes: 1, myReaction: 0 });
+  root.querySelector("[data-reaction='1']").click();
+  await flush();
+  expect(request).toHaveBeenLastCalledWith("react", { id: ROOT, value: 0 });
+});
+
+test("renders comment bodies and nicknames as literal text", async () => {
+  const root = await mount({}, [
+    comment({
+      text: '<img src=x onerror="bad()">\nSecond line',
+      author: { id: PROFILE, nickname: "<script>bad()</script>" },
+    }),
+  ]);
+  expect(root.querySelector(".ryd-discussion-comment-text").textContent).toContain("<img");
+  expect(root.querySelector("img, script")).toBeNull();
+});
+
+test("keeps a failed submission draft and reuses its idempotency ID on retry", async () => {
+  const root = await mount({ session });
+  const form = root.querySelector(".ryd-discussion-composer form");
+  request.mockRejectedValueOnce({ code: "unavailable" });
+  submit(form, "A new comment");
+  await flush();
+  const first = request.mock.calls.find(([operation]) => operation === "createComment")[1];
+  expect(form.querySelector("textarea").value).toBe("A new comment");
+  request.mockResolvedValueOnce(comment({ text: "A new comment" }));
+  form.dispatchEvent(new Event("submit", { bubbles: true, cancelable: true }));
+  await flush();
+  const creates = request.mock.calls.filter(([operation]) => operation === "createComment");
+  expect(creates).toHaveLength(2);
+  expect(creates[1][1].requestId).toBe(first.requestId);
+  expect(first).toMatchObject({ videoId: VIDEO, text: "A new comment" });
+});
+
+test("guards blank posts and duplicate clicks while saving", async () => {
+  const root = await mount({ session });
+  const form = root.querySelector(".ryd-discussion-composer form");
+  submit(form, "    ");
+  expect(request.mock.calls.filter(([operation]) => operation === "createComment")).toHaveLength(0);
+  let resolve;
+  request.mockImplementationOnce(
+    () =>
+      new Promise((done) => {
+        resolve = done;
+      }),
+  );
+  submit(form, "Hello");
+  form.dispatchEvent(new Event("submit", { bubbles: true, cancelable: true }));
+  expect(request.mock.calls.filter(([operation]) => operation === "createComment")).toHaveLength(1);
+  resolve(comment());
+  await flush();
+});
+
+test("nickname onboarding persists a chosen nickname without deriving one from account details", async () => {
+  const root = await mount({
+    session: { ...session, profile: null, fullName: "Private Name", email: "private@example.test" },
+  });
+  const input = root.querySelector("input[name='nickname']");
+  expect(input.value).toBe("");
+  expect(root.textContent).not.toContain("private@example.test");
+  input.value = "New Writer";
+  request.mockResolvedValueOnce({ ...session, profile: { id: PROFILE, nickname: "New Writer" } });
+  input.closest("form").dispatchEvent(new Event("submit", { bubbles: true, cancelable: true }));
+  await flush();
+  expect(request).toHaveBeenLastCalledWith("profile", { nickname: "New Writer" });
+  expect(root.querySelector("textarea[name='comment']")).not.toBeNull();
+});
+
+test("inactive members retain their own edit/delete controls while another account does not", async () => {
+  const root = await mount({ session: { ...session, canPost: false } });
+  expect(root.querySelector("[data-action='edit']")).not.toBeNull();
+  expect(root.querySelector("[data-action='delete']")).not.toBeNull();
+  panel.setSession({ ...session, profile: { id: REPLY, nickname: "Other" } });
+  expect(root.querySelector("[data-action='edit']")).toBeNull();
+  panel.setSession({ authenticated: false, profile: null });
+  expect(root.querySelector("[data-action='report']")).toBeNull();
+});
+
+test("a nickname request finishing after logout cannot restore the previous account composer", async () => {
+  const root = await mount({ session: { ...session, profile: null } });
+  let resolve;
+  request.mockImplementationOnce(
+    () =>
+      new Promise((done) => {
+        resolve = done;
+      }),
+  );
+  const input = root.querySelector("input[name='nickname']");
+  input.value = "Writer";
+  input.closest("form").dispatchEvent(new Event("submit", { bubbles: true, cancelable: true }));
+  panel.setSession({ authenticated: false, canPost: false, profile: null });
+  resolve(session);
+  await flush();
+  expect(root.querySelector("textarea[name='comment']")).toBeNull();
+  expect(root.querySelector("[data-action='inbox']").hidden).toBe(true);
+});
+
+test("signing in refreshes ownership flags previously fetched while signed out", async () => {
+  const root = await mount({}, [comment({ canEdit: false, canDelete: false })]);
+  request.mockResolvedValueOnce({ items: [comment()], nextCursor: null });
+  panel.setSession(session);
+  await flush();
+  expect(request).toHaveBeenLastCalledWith("comments", { videoId: VIDEO, sort: "top" });
+  expect(root.querySelector("[data-action='edit']")).not.toBeNull();
+});
+
+test("deletion waits for explicit inline confirmation and shows a tombstone", async () => {
+  const root = await mount({ session });
+  root.querySelector("[data-action='delete']").click();
+  expect(request.mock.calls.some(([operation]) => operation === "deleteComment")).toBe(false);
+  request.mockResolvedValueOnce(comment({ deleted: true, text: "", author: null }));
+  root.querySelector("[data-action='confirm-delete']").click();
+  await flush();
+  expect(request).toHaveBeenLastCalledWith("deleteComment", { id: ROOT });
+  expect(root.querySelector(".ryd-discussion-comment-text").textContent).toBe(discussionText("deleted"));
+});
+
+test("replies preserve the root and immediate target IDs", async () => {
+  const root = await mount({ session }, [comment({ replyCount: 1 })]);
+  request.mockResolvedValueOnce({
+    items: [comment({ id: REPLY, parentId: ROOT, replyToId: ROOT, text: "First reply" })],
+    nextCursor: null,
+  });
+  root.querySelector("[data-action='load-replies']").click();
+  await flush();
+  const reply = root.querySelector(`[data-comment-id='${REPLY}']`);
+  reply.querySelector("[data-action='reply']").click();
+  request.mockResolvedValueOnce(
+    comment({ id: "55555555-5555-5555-5555-555555555555", parentId: ROOT, replyToId: REPLY }),
+  );
+  submit(reply.querySelector("form"), "Nested response");
+  await flush();
+  expect(request.mock.calls.find(([operation]) => operation === "createComment")[1]).toMatchObject({
+    parentId: ROOT,
+    replyToId: REPLY,
+    text: "Nested response",
+  });
+  expect(root.querySelectorAll(".ryd-discussion-reply")).toHaveLength(2);
+});
+
+test("posting a reply preserves loaded pages and merges the next page without duplicating the new reply", async () => {
+  const previous = Array.from({ length: 21 }, (_, index) =>
+    comment({
+      id: `${String(index + 10).padStart(8, "0")}-1111-4111-8111-111111111111`,
+      parentId: ROOT,
+      replyToId: ROOT,
+      text: `Reply ${index + 1}`,
+      createdAt: `2026-09-01T12:00:${String(index).padStart(2, "0")}Z`,
+    }),
+  );
+  const created = comment({
+    id: REPLY,
+    parentId: ROOT,
+    replyToId: ROOT,
+    text: "Newest reply",
+    createdAt: "2026-09-01T12:01:00Z",
+  });
+  const root = await mount({ session }, [comment({ replyCount: 21 })]);
+  request.mockImplementation(async (operation, payload) => {
+    if (operation === "createComment") return created;
+    if (operation === "replies")
+      return payload.cursor
+        ? { items: [previous[20], created], nextCursor: null }
+        : { items: previous.slice(0, 20), nextCursor: "remaining-replies" };
+    return { items: [], nextCursor: null };
+  });
+  root.querySelector("[data-action='load-replies']").click();
+  await flush();
+  root.querySelector("[data-action='reply']").click();
+  submit(root.querySelector(".ryd-discussion-inline-editor form"), created.text);
+  await flush();
+  expect(root.querySelectorAll(".ryd-discussion-reply")).toHaveLength(21);
+  expect(root.querySelector(`[data-comment-id='${REPLY}']`).textContent).toContain(created.text);
+  expect(request.mock.calls.filter(([operation]) => operation === "replies")).toHaveLength(1);
+  root.querySelector(".ryd-discussion-replies > button").click();
+  await flush();
+  expect(request).toHaveBeenLastCalledWith("replies", { rootId: ROOT, cursor: "remaining-replies" });
+  expect([...root.querySelectorAll(".ryd-discussion-reply")].map((row) => row.dataset.commentId)).toEqual([
+    ...previous.map((item) => item.id),
+    REPLY,
+  ]);
+});
+
+test("posting while the first reply page is loading keeps the new reply when that page arrives", async () => {
+  const thread = comment({ replyCount: 1 });
+  const root = await mount({ session }, [thread]);
+  const previous = comment({ id: REPLY, parentId: ROOT, replyToId: ROOT, text: "Previous reply" });
+  const created = comment({
+    id: "55555555-5555-4555-8555-555555555555",
+    parentId: ROOT,
+    replyToId: ROOT,
+    text: "New reply",
+    createdAt: "2026-09-01T12:00:00.001Z",
+  });
+  let resolveReplies;
+  request.mockImplementation((operation) => {
+    if (operation === "replies")
+      return new Promise((resolve) => {
+        resolveReplies = resolve;
+      });
+    return Promise.resolve(created);
+  });
+  root.querySelector("[data-action='load-replies']").click();
+  root.querySelector("[data-action='reply']").click();
+  submit(root.querySelector(".ryd-discussion-inline-editor form"), created.text);
+  await flush();
+  expect(root.querySelector(`[data-comment-id='${created.id}']`)).not.toBeNull();
+  resolveReplies({ items: [previous], nextCursor: null });
+  await flush();
+  expect([...root.querySelectorAll(".ryd-discussion-reply")].map((row) => row.dataset.commentId)).toEqual([
+    REPLY,
+    created.id,
+  ]);
+  expect(thread.replyCount).toBe(2);
+});
+
+test("a reply to an unopened thread remains visible and lets a failed history fetch be retried", async () => {
+  const root = await mount({ session }, [comment({ replyCount: 0 })]);
+  const previous = comment({ id: REPLY, parentId: ROOT, replyToId: ROOT, text: "Earlier reply" });
+  const created = comment({
+    id: "55555555-5555-4555-8555-555555555555",
+    parentId: ROOT,
+    replyToId: ROOT,
+    text: "New reply",
+    createdAt: "2026-09-01T12:01:00Z",
+  });
+  request.mockResolvedValueOnce(created).mockRejectedValueOnce({ code: "unavailable" });
+  root.querySelector("[data-action='reply']").click();
+  submit(root.querySelector(".ryd-discussion-inline-editor form"), created.text);
+  await flush();
+  expect(root.querySelector(`[data-comment-id='${created.id}']`)).not.toBeNull();
+  const showReplies = root.querySelector("[data-action='load-replies']");
+  expect(showReplies.hidden).toBe(false);
+  expect(showReplies.disabled).toBe(false);
+  request.mockResolvedValueOnce({ items: [previous, created], nextCursor: null });
+  showReplies.click();
+  await flush();
+  expect([...root.querySelectorAll(".ryd-discussion-reply")].map((row) => row.dataset.commentId)).toEqual([
+    REPLY,
+    created.id,
+  ]);
+  expect(showReplies.hidden).toBe(true);
+});
+
+test("posting fetches unopened history even when the root count predates another user's reply", async () => {
+  const thread = comment();
+  const root = await mount({ session }, [thread]);
+  const previous = comment({
+    id: "55555555-5555-4555-8555-555555555555",
+    parentId: ROOT,
+    replyToId: ROOT,
+    text: "Another user's reply",
+    createdAt: "2026-09-01T12:00:00Z",
+  });
+  const created = comment({ id: REPLY, parentId: ROOT, replyToId: ROOT, text: "First reply" });
+  request.mockResolvedValueOnce(created).mockResolvedValueOnce({ items: [previous, created], nextCursor: null });
+  root.querySelector("[data-action='reply']").click();
+  submit(root.querySelector(".ryd-discussion-inline-editor form"), created.text);
+  await flush();
+  expect(root.querySelector(`[data-comment-id='${REPLY}']`)).not.toBeNull();
+  expect(root.querySelector(`[data-comment-id='${previous.id}']`)).not.toBeNull();
+  expect(request).toHaveBeenLastCalledWith("replies", { rootId: ROOT });
+  expect(thread.replyCount).toBe(2);
+});
+
+test("top/new sorting discards the prior pagination cursor", async () => {
+  const root = await mount();
+  const sort = root.querySelector("select");
+  sort.value = "new";
+  sort.dispatchEvent(new Event("change"));
+  await flush();
+  expect(request).toHaveBeenLastCalledWith("comments", { videoId: VIDEO, sort: "new" });
+});
+
+test("an obsolete response cannot render after panel destruction", async () => {
+  const root = await mount();
+  let resolve;
+  request.mockImplementationOnce(
+    () =>
+      new Promise((done) => {
+        resolve = done;
+      }),
+  );
+  const loading = panel.load();
+  panel.destroy();
+  resolve({ items: [comment({ text: "Late response" })] });
+  await loading;
+  expect(root.textContent).not.toContain("Late response");
+  expect(document.getElementById("ryd-discussion-panel")).toBeNull();
+});
+
+test("moderators can review reports and issue explicit scoped actions", async () => {
+  const root = await mount({ session: { ...session, isModerator: true } });
+  request.mockResolvedValueOnce({
+    items: [{ id: REPLY, comment: comment(), reason: "spam", authorSuspended: false }],
+    nextCursor: null,
+  });
+  root.querySelector("[data-action='moderation']").click();
+  await flush();
+  request.mockResolvedValueOnce(comment({ hidden: true }));
+  root.querySelector("[data-action='hide']").click();
+  await flush();
+  expect(request.mock.calls).toContainEqual(["moderateComment", { id: ROOT, hidden: true }]);
+});
+
+test("Russian UI follows the YouTube document language", async () => {
+  document.documentElement.lang = "ru-RU";
+  const root = await mount({ session });
+  expect(root.querySelector("h2").textContent).toBe("Комментарии RYD");
+  expect(root.querySelector("[data-action='post']").textContent).toBe("Отправить");
+  expect(root.querySelector("[data-reaction='1']").getAttribute("aria-label")).toContain("Нравится");
+});
+
+test("moderators can restore comments and authoring from dismissed report history", async () => {
+  const root = await mount({ session: { ...session, isModerator: true } });
+  request.mockImplementation(async (operation, payload) => {
+    if (operation === "reports" && payload.status === "resolved")
+      return { items: [{ id: REPLY, comment: comment({ hidden: true }), reason: "spam", authorSuspended: true }] };
+    return { items: [] };
+  });
+  root.querySelector("[data-action='moderation']").click();
+  await flush();
+  const filter = root.querySelector("[data-action='report-status']");
+  filter.value = "resolved";
+  filter.dispatchEvent(new Event("change"));
+  await flush();
+  expect(root.querySelector("[data-action='dismiss']")).toBeNull();
+  expect(root.querySelector("[data-action='unban']")).not.toBeNull();
+  root.querySelector("[data-action='restore']").click();
+  await flush();
+  expect(request.mock.calls).toContainEqual(["moderateComment", { id: ROOT, hidden: false }]);
+  expect(root.querySelector("[data-action='report-status']").value).toBe("resolved");
+});
diff --git a/Extensions/combined/src/discussion/popup.js b/Extensions/combined/src/discussion/popup.js
new file mode 100644
index 0000000..4c3cf51
--- /dev/null
+++ b/Extensions/combined/src/discussion/popup.js
@@ -0,0 +1,54 @@
+import { requestDiscussion, subscribeDiscussionEvents } from "./client";
+import { createDiscussionInbox } from "./inbox";
+import { discussionText as t } from "./localize";
+
+export function initDiscussionPopup() {
+  const root = document.getElementById("ryd-discussion-popup");
+  if (!root) return;
+  if (!document.documentElement.lang && chrome.i18n?.getUILanguage)
+    document.documentElement.lang = chrome.i18n.getUILanguage();
+  const toggle = document.getElementById("ryd-discussion-inbox-toggle");
+  const inbox = createDiscussionInbox({ authenticated: false });
+  root.append(inbox.node);
+  inbox.node.hidden = true;
+  toggle.textContent = t("notifications");
+  toggle.addEventListener("click", () => {
+    inbox.node.hidden = !inbox.node.hidden;
+    toggle.setAttribute("aria-expanded", String(!inbox.node.hidden));
+    if (!inbox.node.hidden) inbox.load();
+  });
+  let generation = 0;
+  const unsubscribe = subscribeDiscussionEvents((event) => {
+    if (event.type === "session") {
+      generation++;
+      inbox.setSession(event.data);
+    }
+    if (event.type === "inbox") {
+      inbox.update(event.data, { live: true });
+      toggle.textContent = `${t("notifications")}${event.data?.unreadCount ? ` (${event.data.unreadCount})` : ""}`;
+    }
+  });
+  const initial = generation;
+  requestDiscussion("session")
+    .then((session) => {
+      if (initial !== generation) return;
+      inbox.setSession(session);
+      if (session.authenticated)
+        requestDiscussion("notifications")
+          .then((value) => {
+            if (initial !== generation) return;
+            inbox.update(value);
+            toggle.textContent = `${t("notifications")}${value?.unreadCount ? ` (${value.unreadCount})` : ""}`;
+          })
+          .catch(() => {});
+    })
+    .catch(() => {});
+  window.addEventListener(
+    "unload",
+    () => {
+      inbox.destroy();
+      unsubscribe();
+    },
+    { once: true },
+  );
+}
diff --git a/Extensions/common/vote-client.js b/Extensions/common/vote-client.js
index fce7e2e..5a00811 100644
--- a/Extensions/common/vote-client.js
+++ b/Extensions/common/vote-client.js
@@ -311,7 +311,12 @@ function createVoteClient({
     return current;
   }
 
-  return { ensureRegistered, submitVote };
+  async function getRegisteredUser() {
+    const credential = await credentialStore.load();
+    return isConfirmedCredential(credential) ? { userId: credential.userId } : null;
+  }
+
+  return { ensureRegistered, getRegisteredUser, submitVote };
 }
 
 export { DEFAULT_API_BASE_URL, VoteClientError, countLeadingZeroes, generateUserId, solvePuzzle, createVoteClient };
diff --git a/Extensions/common/vote-client.spec.js b/Extensions/common/vote-client.spec.js
index 94a1e0a..b34a63b 100644
--- a/Extensions/common/vote-client.spec.js
+++ b/Extensions/common/vote-client.spec.js
@@ -8,6 +8,28 @@ const CHALLENGE = Buffer.alloc(16, 7).toString("base64");
 const ZERO_SOLUTION = "AAAAAA==";
 const GENERATED_USER_ID = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghij";
 
+test.each([null, { userId: GENERATED_USER_ID, registrationConfirmed: false }])(
+  "reading an existing voter does not create or register an identity: %s",
+  async (credentials) => {
+    const store = createCredentialStore(credentials);
+    const fetchImpl = jest.fn();
+    const cryptoImpl = createCryptoImpl();
+    const client = createClient({ credentialStore: store, fetchImpl, cryptoImpl });
+    expect(await client.getRegisteredUser()).toBe(null);
+    expect(fetchImpl).not.toHaveBeenCalled();
+    expect(store.save).not.toHaveBeenCalled();
+    expect(cryptoImpl.getRandomValues).not.toHaveBeenCalled();
+  },
+);
+
+test("reads a confirmed existing voter without registration", async () => {
+  const store = createCredentialStore({ userId: GENERATED_USER_ID, registrationConfirmed: true });
+  const fetchImpl = jest.fn();
+  const client = createClient({ credentialStore: store, fetchImpl });
+  expect(await client.getRegisteredUser()).toEqual({ userId: GENERATED_USER_ID });
+  expect(fetchImpl).not.toHaveBeenCalled();
+});
+
 function jsonResponse(body, status = 200) {
   return {
     ok: status >= 200 && status < 300,
diff --git a/Extensions/e2e/discussion/README.md b/Extensions/e2e/discussion/README.md
new file mode 100644
index 0000000..1e11b5a
--- /dev/null
+++ b/Extensions/e2e/discussion/README.md
@@ -0,0 +1,51 @@
+# Discussion browser validation
+
+`hermetic-discussion-smoke.js` loads the generated MV3 extension through the shared
+`HermeticExtensionArtifactAdapter` in a new, disposable headless Chromium profile.
+It serves fixture documents at YouTube URLs and uses the loopback discussion host
+at `http://127.0.0.1:5099`. It never attaches to an existing browser profile.
+
+Start the repository's local discussion fixture host, then build a dedicated artifact:
+
+```powershell
+node node_modules/webpack-cli/bin/cli.js --mode=production --env liveTest=true --env discussionTestOrigin=http://127.0.0.1:5099 --output-path test-results/discussion/generated
+node Extensions/e2e/discussion/hermetic-discussion-smoke.js
+```
+
+Use Node 22.17.0. `RYD_DISCUSSION_ARTIFACT` can select another generated local-test
+Chrome artifact; `RYD_DISCUSSION_OUTPUT` can select a fresh evidence directory.
+The default output creates a new timestamped directory under `test-results/discussion`.
+Set `RYD_DISCUSSION_NOTIFICATIONS_ONLY=true` for a focused notification/reconnect
+run with only the required rendered-panel, nickname, and comment prerequisites.
+Between reply and like delivery, that run closes the actual worker WebSocket,
+asserts its native close event, and requires a new open connection with a different
+server ticket. Only the ticket-change boolean is recorded; ticket values are never
+returned from the worker or saved in evidence.
+
+The smoke asserts English and Russian watch and Shorts rendering, nickname updates,
+comment and reply creation, public reactions through like/dislike/removal, author
+controls after account switches, and premium/supporter/inactive posting gates.
+It checks light and dark fallback styles without native YouTube color variables,
+a 390-pixel viewport, Shorts Escape/Enter handling, enabled native comments exclusion,
+explicit current-video kids exclusion, and continued rendering when only unrelated
+recommendations or advertisements have kids flags.
+
+It also exercises report submission, moderator hide/ban/dismiss, resolved report
+history, and restoration/unbanning. Incoming replies and likes must produce a real
+worker WebSocket `NotificationsChanged` frame and a corresponding runtime inbox
+event before the runner explicitly reads the inbox. A test-only WebSocket observer
+forwards the native constructor unchanged and records only connection sequence,
+event target, and revision. Inbox UI mark-read is verified against the local API.
+
+All account changes use seeded fixture identities in dedicated discussion test keys.
+Created comments and replies are deleted after the attempt. The fixture host keeps
+its local audit history and chosen fixture nicknames. The existing adapter redirects
+legacy extension API traffic to its fake server, blocks external name resolution
+before browser startup, and cleans up its temporary artifact and profile. The
+compiled discussion runtime continues to use its explicitly configured local API.
+
+Each attempt records a sanitized JSON result, operation ledger, and 36 screenshots.
+The report labels this evidence as hermetic. It does not prove behavior against live
+YouTube, live OAuth accounts, actual YouTube language switching, cross-tab toast
+deduplication, Firefox, or Safari. Use the separate `live-discussion-contract.js`
+only for an authorized live session and its specified local mutation boundary.
diff --git a/Extensions/e2e/discussion/hermetic-discussion-smoke.js b/Extensions/e2e/discussion/hermetic-discussion-smoke.js
new file mode 100644
index 0000000..c3bbf1c
--- /dev/null
+++ b/Extensions/e2e/discussion/hermetic-discussion-smoke.js
@@ -0,0 +1,712 @@
+const assert = require("node:assert/strict");
+const crypto = require("node:crypto");
+const fs = require("node:fs/promises");
+const path = require("node:path");
+const { expect } = require("@playwright/test");
+const { HermeticExtensionArtifactAdapter, startHermeticApiServer } = require("../hermetic-artifact-smoke");
+const { bounded, localClient, poll, solve, TIMEOUT_MS } = require("./live-discussion-contract");
+
+const REPOSITORY = path.resolve(__dirname, "../../..");
+const ORIGIN = "http://127.0.0.1:5099";
+const LANGUAGES = ["en", "ru"];
+const SURFACES = ["watch", "shorts"];
+
+function fixture({ language, surface, videoId, disabled = true, kids = false, dark = true }) {
+  assert.ok(LANGUAGES.includes(language) && SURFACES.includes(surface));
+  assert.match(videoId, /^[A-Za-z0-9_-]{11}$/);
+  const options = JSON.stringify({ language, surface, videoId, disabled, kids });
+  return `<!doctype html><html lang="${language}"${dark ? " dark" : ""}><head>
+    <meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1">
+    <title>Discussion artifact fixture</title><style>
+    *{box-sizing:border-box} body{margin:0;padding:24px;font:14px Arial,sans-serif;background:${dark ? "#0f0f0f" : "#fff"};color:${dark ? "#f1f1f1" : "#0f0f0f"}}
+    [hidden]{display:none!important} ytd-watch-flexy,ytd-reel-video-renderer,ytd-comments,reel-action-bar-view-model{display:block}
+    ytd-watch-flexy{width:min(920px,100%);margin:auto} ytd-comments{min-height:42px;margin-top:20px}
+    #movie_player{height:120px;background:#222;margin-bottom:20px} #shorts-player{height:280px;background:#222;width:260px}
+    ytd-reel-video-renderer{width:320px;max-width:100%;height:500px;margin:auto} reel-action-bar-view-model{min-height:80px}
+    </style></head><body><main id="fixture-root"></main><script>
+    (()=>{const o=${options};const root=document.createElement(o.surface==='watch'?'ytd-watch-flexy':'ytd-reel-video-renderer');
+    const player=document.createElement('div');player.id=o.surface==='watch'?'movie_player':'shorts-player';
+    player.getVideoData=()=>({video_id:o.videoId});player.getPlayerResponse=()=>({videoDetails:{videoId:o.videoId,...(o.kids?{isMadeForKids:true}:{})},
+    endscreen:{videos:[{videoId:'OtherVideo1',isMadeForKids:true}]},adPlacements:[{videoDetails:{videoId:'OtherVideo2',madeForKids:true}}],
+    microformat:{playerMicroformatRenderer:{recommendations:[{isMadeForKids:true}]}}});
+    root.append(player);root.polymerController={data:o.kids?{isMadeForKids:true}:{}};
+    if(o.surface==='watch'){root.setAttribute('video-id',o.videoId);const comments=document.createElement('ytd-comments');
+    comments.textContent=o.disabled?(o.language==='ru'?'Комментарии отключены.':'Comments are turned off.'):'Native comments enabled';
+    comments.polymerController={data:{contents:o.disabled?[{messageRenderer:{text:{runs:[{navigationEndpoint:{urlEndpoint:{url:'https://support.google.com/youtube/answer/9706180?hl='+o.language}}}]}}}]:[]}};root.append(comments);}
+    else{const actions=document.createElement('reel-action-bar-view-model');actions.polymerController={data:{buttonViewModels:[{buttonViewModel:{iconName:'SHORTS_COMMENT',state:o.disabled?'BUTTON_VIEW_MODEL_STATE_DISABLED':'BUTTON_VIEW_MODEL_STATE_ENABLED'}}]}};root.append(actions);}
+    document.querySelector('#fixture-root').append(root);window.ytInitialPlayerResponse=player.getPlayerResponse();
+    window.__discussionFixture={setKids(value){root.polymerController.data=value?{isMadeForKids:true}:{};o.kids=value;window.ytInitialPlayerResponse=player.getPlayerResponse();document.dispatchEvent(new Event('yt-page-data-updated'));},
+    setLanguage(value){document.documentElement.lang=value;document.dispatchEvent(new Event('yt-page-data-updated'));}};
+    })();</script></body></html>`;
+}
+
+async function runHermeticDiscussionSmoke({
+  artifactDirectory = process.env.RYD_DISCUSSION_ARTIFACT ||
+    path.join(REPOSITORY, "test-results/discussion/generated/chrome"),
+  outputDirectory = process.env.RYD_DISCUSSION_OUTPUT ||
+    path.join(REPOSITORY, `test-results/discussion/hermetic-smoke-${Date.now()}`),
+  notificationFocus = process.env.RYD_DISCUSSION_NOTIFICATIONS_ONLY === "true",
+} = {}) {
+  const healthResponse = await fetch(`${ORIGIN}/api/discussion/local/health`, {
+    signal: AbortSignal.timeout(TIMEOUT_MS),
+  });
+  assert.equal(healthResponse.status, 200);
+  assert.equal((await healthResponse.json()).localTestMode, true, "Local discussion host is required");
+  const marker = JSON.parse(await fs.readFile(path.join(artifactDirectory, "live-build.json"), "utf8"));
+  assert.match(marker.buildId, /^[a-f0-9]{32}$/);
+  const background = await fs.readFile(path.join(artifactDirectory, "ryd.background.js"), "utf8");
+  assert.ok(background.includes(`const testOrigin =  true ? "${ORIGIN}"`), "Requires an explicit local-test build");
+  await fs.mkdir(outputDirectory, { recursive: true });
+  const seedResponse = await fetch(`${ORIGIN}/api/discussion/local/seed`, {
+    method: "POST",
+    signal: AbortSignal.timeout(TIMEOUT_MS),
+  });
+  assert.equal(seedResponse.status, 200);
+  const { accounts } = await seedResponse.json();
+  const ledger = [];
+  const request = localClient(ORIGIN, accounts, (value) => ledger.push(value));
+  const results = [];
+  const screenshots = [];
+  const errors = [];
+  const created = [];
+  const profilesToRestore = new Set();
+  const commentsToRestore = new Set();
+  const record = (name, detail = {}) => {
+    results.push({ name, passed: true, ...detail });
+    process.stdout.write(`PASS ${name}\n`);
+  };
+  const apiServer = await startHermeticApiServer();
+  const adapter = new HermeticExtensionArtifactAdapter({
+    apiServer,
+    artifactDirectory,
+    headless: true,
+    contextOptions: { viewport: { width: 1200, height: 900 } },
+  });
+  let currentFixture;
+  let popup;
+  let failure;
+  try {
+    await adapter.start();
+    const { context, page, worker } = adapter;
+    context.setDefaultTimeout(TIMEOUT_MS);
+    context.setDefaultNavigationTimeout(TIMEOUT_MS);
+    page.on("pageerror", (error) => errors.push({ name: error.name, message: error.message.slice(0, 200) }));
+    await worker.evaluate(() => {
+      const NativeWebSocket = globalThis.WebSocket;
+      const probe = {
+        sequence: 0,
+        connection: 0,
+        ticketChanges: 0,
+        events: [],
+        closed: [],
+        ready: new Set(),
+        sockets: new Map(),
+      };
+      let previousTicket = null;
+      globalThis.__rydDiscussionSocketProbe = probe;
+      globalThis.WebSocket = class extends NativeWebSocket {
+        constructor(...args) {
+          super(...args);
+          const url = new URL(args[0]);
+          if (url.origin !== "ws://127.0.0.1:5099" || url.pathname !== "/api/discussion/notifications/hub") return;
+          const connection = ++probe.connection;
+          const ticket = url.searchParams.get("access_token");
+          if (previousTicket !== null && ticket && ticket !== previousTicket) probe.ticketChanges++;
+          previousTicket = ticket;
+          probe.sockets.set(connection, this);
+          this.addEventListener("message", (event) => {
+            for (const packet of String(event.data).split("\u001e")) {
+              let message;
+              try {
+                message = JSON.parse(packet);
+              } catch {
+                continue;
+              }
+              if (message && Object.keys(message).length === 0) probe.ready.add(connection);
+              if (message.target !== "NotificationsChanged" || !/^\d+$/.test(message.arguments?.[0]?.revision))
+                continue;
+              probe.events.push({
+                sequence: ++probe.sequence,
+                connection,
+                target: message.target,
+                revision: message.arguments[0].revision,
+              });
+              if (probe.events.length > 100) probe.events.shift();
+            }
+          });
+          this.addEventListener("close", (event) => {
+            probe.closed.push({ connection, code: event.code });
+            probe.ready.delete(connection);
+            probe.sockets.delete(connection);
+          });
+        }
+      };
+    });
+    await context.route(`${ORIGIN}/**`, (route) => route.continue());
+    await context.route("https://www.youtube.com/**", (route) => {
+      const url = new URL(route.request().url());
+      if (
+        route.request().resourceType() === "document" &&
+        ["/watch", `/shorts/${currentFixture?.videoId}`].includes(url.pathname)
+      )
+        return route.fulfill({ contentType: "text/html", body: fixture(currentFixture) });
+      return route.fulfill({ status: 404, body: "Fixture resource absent" });
+    });
+    popup = await context.newPage();
+    await popup.goto(`chrome-extension://${adapter.extensionId}/popup.html`, { waitUntil: "domcontentloaded" });
+    await popup.evaluate(() => {
+      const probe = { sequence: 0, events: [] };
+      globalThis.__rydDiscussionInboxProbe = probe;
+      chrome.runtime.onMessage.addListener((message, sender) => {
+        if (sender.id !== chrome.runtime.id || message.message !== "ryd_discussion_event" || message.type !== "inbox")
+          return;
+        probe.events.push({
+          sequence: ++probe.sequence,
+          revision: message.data.revision,
+          items: (message.data.items || []).map((item) => ({
+            id: item.id,
+            commentId: item.commentId,
+            type: item.type,
+            read: item.read,
+            revision: item.revision,
+          })),
+        });
+        if (probe.events.length > 100) probe.events.shift();
+      });
+    });
+    const operation = (name, payload = {}) =>
+      bounded(
+        () =>
+          popup.evaluate(
+            ({ name, payload }) => chrome.runtime.sendMessage({ message: "ryd_discussion", operation: name, payload }),
+            { name, payload },
+          ),
+        `Worker ${name}`,
+      );
+    async function setAccount(name) {
+      let expectedProfile = null;
+      if (name) {
+        const session = await request("/me", { account: name });
+        expectedProfile = session.profile?.id || null;
+      }
+      await bounded(
+        () =>
+          worker.evaluate(
+            ({ account, voter }) =>
+              chrome.storage.local.set({
+                rydDiscussionTestAuth: account ? { sessionToken: account.sessionToken } : null,
+                rydDiscussionTestCredentials: { userId: voter, registrationConfirmed: true },
+              }),
+            { account: name ? accounts[name] : null, voter: accounts.commenter.voterId },
+          ),
+        "Set fixture account",
+      );
+      const result = await poll(
+        () => operation("session"),
+        (value) =>
+          value.ok &&
+          (name
+            ? value.data.authenticated &&
+              (value.data.profile?.id || null) === expectedProfile &&
+              value.data.membershipTier ===
+                {
+                  commenter: "commenter",
+                  other: "commenter",
+                  premium: "premium",
+                  moderator: "premium",
+                  supporter: "supporter",
+                  inactive: "none",
+                }[name]
+            : !value.data.authenticated),
+        "Fixture session did not converge",
+      );
+      const refresh = page.locator(".ryd-discussion-thread > .ryd-discussion-toolbar > button");
+      if (await refresh.count()) await expect(refresh).toBeEnabled();
+      return result;
+    }
+    const socketSnapshot = () =>
+      bounded(
+        () =>
+          worker.evaluate(() => {
+            const probe = globalThis.__rydDiscussionSocketProbe;
+            return {
+              connection: probe.connection,
+              ticketChanges: probe.ticketChanges,
+              closed: probe.closed,
+              ready: [...probe.ready],
+              events: probe.events,
+              open: [...probe.sockets].filter(([, socket]) => socket.readyState === 1).map(([id]) => id),
+            };
+          }),
+        "Observe native SignalR frames",
+      );
+    const inboxSnapshot = () =>
+      bounded(() => popup.evaluate(() => globalThis.__rydDiscussionInboxProbe), "Observe runtime inbox events");
+    const root = () => page.locator("#ryd-discussion-panel, #ryd-discussion-drawer").filter({ visible: true });
+    const row = (id) => root().locator(`[data-comment-id="${id}"]`);
+    const composer = () => root().locator(".ryd-discussion-composer");
+    async function open(options) {
+      currentFixture = options;
+      await page.goto(
+        `https://www.youtube.com/${options.surface === "watch" ? `watch?v=${options.videoId}` : `shorts/${options.videoId}`}`,
+        { waitUntil: "domcontentloaded" },
+      );
+      await expect(page.locator("html")).toHaveAttribute("data-ryd-extension-build", marker.buildId);
+      if (options.kids || options.disabled === false) return;
+      if (options.surface === "shorts") await page.locator("#ryd-discussion-launcher").click();
+      await expect(root()).toHaveCount(1);
+      await expect(root()).toHaveAttribute("data-video-id", options.videoId);
+    }
+    async function screenshot(name) {
+      const file = `${name}.png`;
+      await page.screenshot({ path: path.join(outputDirectory, file), timeout: TIMEOUT_MS });
+      screenshots.push(file);
+    }
+    async function narrowScreenshot(name) {
+      const viewport = page.viewportSize();
+      try {
+        await page.setViewportSize({ width: 390, height: 844 });
+        const box = await root().boundingBox();
+        assert.ok(box && box.x >= -1 && box.x + box.width <= 391, "Narrow activity panel overflows viewport");
+        await screenshot(`${name}-narrow`);
+      } finally {
+        await page.setViewportSize(viewport);
+      }
+    }
+    async function ownNickname(language, surface) {
+      if (await composer().locator(".ryd-discussion-account button").count())
+        await composer().locator(".ryd-discussion-account button").click();
+      const nickname = `Artifact ${language} ${surface} ${crypto.randomBytes(3).toString("hex")}`;
+      await composer().locator('input[name="nickname"]').fill(nickname);
+      await composer().locator('button[type="submit"]').click();
+      await expect(composer().locator(".ryd-discussion-account")).toContainText(nickname);
+      assert.equal((await request("/me", { account: "commenter" })).profile.nickname, nickname);
+      return nickname;
+    }
+    async function createRoot(videoId, text) {
+      await composer().locator("textarea").fill(text);
+      await composer().locator('[data-action="post"]').click();
+      const value = await poll(
+        () => request(`/videos/${videoId}/comments?sort=new`),
+        (list) => list.items.some((item) => item.text === text),
+        "Created comment absent from local API",
+      );
+      const comment = value.items.find((item) => item.text === text);
+      created.push({ id: comment.id, account: "commenter" });
+      await expect(row(comment.id)).toBeVisible();
+      return comment;
+    }
+    async function assertFallback(dark) {
+      await page.evaluate((value) => {
+        document.documentElement.toggleAttribute("dark", value);
+        document.body.style.backgroundColor = value ? "#0f0f0f" : "#fff";
+        document.body.style.color = value ? "#f1f1f1" : "#0f0f0f";
+      }, dark);
+      const colors = await root().evaluate((node) => {
+        const input = node.querySelector("textarea");
+        return {
+          text: getComputedStyle(node).color,
+          input: getComputedStyle(input).backgroundColor,
+          inputText: getComputedStyle(input).color,
+          nativeVariable: getComputedStyle(document.documentElement).getPropertyValue("--yt-spec-text-primary"),
+        };
+      });
+      assert.equal(colors.nativeVariable, "");
+      assert.equal(colors.text, dark ? "rgb(241, 241, 241)" : "rgb(15, 15, 15)");
+      assert.notEqual(colors.input, colors.inputText);
+      return colors;
+    }
+
+    async function ensureProfile(account) {
+      const session = await request("/me", { account });
+      if (!session.profile?.nickname)
+        await request("/me/profile", {
+          account,
+          method: "PUT",
+          body: { nickname: `Artifact ${account} ${crypto.randomBytes(3).toString("hex")}` },
+        });
+    }
+
+    async function moderation(comment, label) {
+      await ensureProfile("other");
+      await ensureProfile("moderator");
+      await setAccount("other");
+      await row(comment.id).locator(':scope > .ryd-discussion-comment-actions [data-action="report"]').click();
+      await row(comment.id)
+        .locator(":scope > .ryd-discussion-inline-editor textarea")
+        .fill(`Artifact moderation ${label}`);
+      await row(comment.id).locator(':scope > .ryd-discussion-inline-editor [data-action="send-report"]').click();
+      const reports = await poll(
+        () => request("/moderation/reports", { account: "moderator" }),
+        (value) => value.items.some((item) => item.comment.id === comment.id),
+        "Report absent from moderator queue",
+      );
+      const reportId = reports.items.find((item) => item.comment.id === comment.id).id;
+      await setAccount("moderator");
+      await root().locator('[data-action="moderation"]').click();
+      const report = () => root().locator(`[data-report-id="${reportId}"]`);
+      await expect(report()).toBeVisible();
+      commentsToRestore.add(comment.id);
+      await report().locator('[data-action="hide"]').click();
+      await expect(report().locator('[data-action="restore"]')).toBeVisible();
+      assert.equal((await request(`/comments/${comment.id}`)).hidden, true);
+      profilesToRestore.add(comment.author.id);
+      await report().locator('[data-action="ban"]').click();
+      await expect(report().locator('[data-action="unban"]')).toBeVisible();
+      assert.equal((await request("/me", { account: "commenter" })).profile.suspended, true);
+      await report().locator('[data-action="dismiss"]').click();
+      await expect(report()).toHaveCount(0);
+      await root().locator('[data-action="report-status"]').selectOption("resolved");
+      await expect(report()).toBeVisible();
+      await expect(report().locator('[data-action="dismiss"]')).toHaveCount(0);
+      await screenshot(`${label}-moderation-history`);
+      await narrowScreenshot(`${label}-moderation-history`);
+      await report().locator('[data-action="restore"]').click();
+      await expect(report().locator('[data-action="hide"]')).toBeVisible();
+      await report().locator('[data-action="unban"]').click();
+      await expect(report().locator('[data-action="ban"]')).toBeVisible();
+      assert.equal((await request(`/comments/${comment.id}`)).hidden, false);
+      assert.equal((await request("/me", { account: "commenter" })).profile.suspended, false);
+      commentsToRestore.delete(comment.id);
+      profilesToRestore.delete(comment.author.id);
+      record(`${label}-report-hide-ban-dismiss-history-restore-unban`, { reportId });
+    }
+
+    async function notifications(comment, label, catalog) {
+      const previousConnection = (await socketSnapshot()).connection;
+      await setAccount("commenter");
+      await root().locator('[data-action="discussion"]').click();
+      await poll(
+        socketSnapshot,
+        (value) => value.open.some((id) => id > previousConnection),
+        "Current fixture SignalR socket did not open",
+      );
+      assert.equal((await operation("readNotifications", { all: true })).ok, true);
+      await page.bringToFront();
+      for (const type of ["reply", "likes"]) {
+        const wireBaseline = await socketSnapshot();
+        const inboxBaseline = await inboxSnapshot();
+        let targetId = comment.id;
+        if (type === "reply") {
+          const reply = await request(`/videos/${comment.videoId}/comments`, {
+            account: "other",
+            method: "POST",
+            body: {
+              text: `Incoming artifact reply ${label} ${crypto.randomUUID()}`,
+              parentId: comment.id,
+              replyToId: comment.id,
+              requestId: crypto.randomUUID(),
+            },
+          });
+          targetId = reply.id;
+          created.push({ id: reply.id, account: "other" });
+        } else {
+          const userId = accounts.other.voterId;
+          const challenge = await request(`/comments/${comment.id}/reaction/challenge`, {
+            method: "POST",
+            body: { userId, value: 1 },
+          });
+          const confirmed = await request(`/comments/${comment.id}/reaction/confirm`, {
+            account: "other",
+            method: "POST",
+            body: {
+              userId,
+              challengeId: challenge.challengeId,
+              solution: solve(challenge.challenge, challenge.difficulty),
+            },
+          });
+          assert.equal(confirmed.myReaction, 1);
+        }
+        const wireSequence = wireBaseline.events.at(-1)?.sequence || 0;
+        await poll(
+          socketSnapshot,
+          (value) =>
+            value.events.some((event) => event.sequence > wireSequence && wireBaseline.open.includes(event.connection)),
+          "No incoming worker SignalR frame for fixture activity",
+        );
+        const observed = await poll(
+          inboxSnapshot,
+          (value) =>
+            value.events.some(
+              (event) =>
+                event.sequence > inboxBaseline.sequence &&
+                event.items.some((item) => item.commentId === targetId && item.type === type && !item.read),
+            ),
+          "No runtime inbox event for the new activity",
+        );
+        const envelope = observed.events.find(
+          (event) =>
+            event.sequence > inboxBaseline.sequence &&
+            event.items.some((item) => item.commentId === targetId && item.type === type && !item.read),
+        );
+        const notification = envelope.items.find(
+          (item) => item.commentId === targetId && item.type === type && !item.read,
+        );
+        const wire = (await socketSnapshot()).events.find(
+          (event) =>
+            event.sequence > wireSequence &&
+            wireBaseline.open.includes(event.connection) &&
+            BigInt(event.revision) >= BigInt(notification.revision),
+        );
+        assert.ok(wire, "Runtime inbox revision has no matching observed SignalR frame");
+        record(`${label}-${type}-native-signalr-and-runtime-inbox`, {
+          wire,
+          notificationId: notification.id,
+          revision: notification.revision,
+        });
+        await root().locator('[data-action="inbox"]').click();
+        const notificationRow = root().locator(`[data-notification-id="${notification.id}"]`);
+        await expect(notificationRow).toBeVisible();
+        if (type === "likes") await expect(notificationRow).toContainText(catalog.discussion_notificationLike.message);
+        await screenshot(`${label}-${type}-inbox`);
+        await narrowScreenshot(`${label}-${type}-inbox`);
+        await notificationRow.locator("button").click();
+        await expect(notificationRow).not.toHaveClass(/is-unread/);
+        await poll(
+          () => request("/notifications", { account: "commenter" }),
+          (value) => value.items.find((item) => item.id === notification.id)?.read === true,
+          "Inbox mark-read did not persist",
+        );
+        record(`${label}-${type}-inbox-ui-and-mark-read`);
+        await root().locator('[data-action="discussion"]').click();
+        if (notificationFocus && type === "reply") {
+          const before = await socketSnapshot();
+          await bounded(
+            () =>
+              worker.evaluate(() => {
+                for (const socket of globalThis.__rydDiscussionSocketProbe.sockets.values()) {
+                  if (socket.readyState === 1) socket.close(4000, "Fixture reconnect");
+                }
+              }),
+            "Close native fixture socket",
+          );
+          const reconnected = await poll(
+            socketSnapshot,
+            (value) =>
+              value.closed.some((entry) => before.open.includes(entry.connection)) &&
+              value.open.some((id) => id > before.connection && value.ready.includes(id)) &&
+              value.ticketChanges > before.ticketChanges,
+            "Worker did not reconnect with a fresh ticket after native socket closure",
+          );
+          record(`${label}-native-socket-close-reconnect-fresh-ticket`, {
+            closedConnections: reconnected.closed.filter((entry) => before.open.includes(entry.connection)),
+            newConnections: reconnected.open.filter((id) => id > before.connection),
+            freshTicket: true,
+          });
+        }
+      }
+    }
+
+    await setAccount(null);
+    for (const language of LANGUAGES) {
+      const catalog = JSON.parse(
+        await fs.readFile(path.join(artifactDirectory, `_locales/${language}/messages.json`), "utf8"),
+      );
+      for (const surface of SURFACES) {
+        const videoId = `H${crypto.randomBytes(8).toString("base64url").slice(0, 10)}`;
+        const label = `${language}-${surface}`;
+        await setAccount(null);
+        await open({ language, surface, videoId, disabled: true, kids: false, dark: true });
+        await expect(root().locator("h2")).toHaveText(catalog.discussion_title.message);
+        await expect(composer().locator("textarea")).toHaveCount(0);
+        await expect(composer()).toContainText(catalog.discussion_gate.message);
+        record(`${label}-anonymous-unknown-kids-unrelated-kids-render`);
+
+        await setAccount("commenter");
+        const nickname = await ownNickname(language, surface);
+        const comment = await createRoot(videoId, `Artifact comment ${label} ${crypto.randomUUID()}`);
+        assert.equal(comment.author.nickname, nickname);
+        record(`${label}-nickname-and-create`);
+
+        if (notificationFocus) {
+          await ensureProfile("other");
+          await setAccount("other");
+          await notifications(comment, label, catalog);
+          continue;
+        }
+
+        await row(comment.id).locator(':scope > .ryd-discussion-comment-actions [data-action="reply"]').click();
+        const replyText = `Artifact reply ${label} ${crypto.randomUUID()}`;
+        await row(comment.id).locator(":scope > .ryd-discussion-inline-editor textarea").fill(replyText);
+        await row(comment.id).locator(':scope > .ryd-discussion-inline-editor [data-action="post"]').click();
+        const replies = await poll(
+          () => request(`/comments/${comment.id}/replies`),
+          (value) => value.items.some((item) => item.text === replyText),
+          "Reply absent from local API",
+        );
+        const reply = replies.items.find((item) => item.text === replyText);
+        created.push({ id: reply.id, account: "commenter" });
+        assert.equal(reply.parentId, comment.id);
+        await expect(row(reply.id)).toBeVisible();
+        record(`${label}-reply`);
+
+        const darkColors = await assertFallback(true);
+        await screenshot(`${label}-dark`);
+        const lightColors = await assertFallback(false);
+        await screenshot(`${label}-light`);
+        record(`${label}-theme-fallback`, { darkColors, lightColors });
+        await assertFallback(true);
+
+        for (const account of ["premium", "supporter", "inactive"]) {
+          await setAccount(account);
+          if (account === "premium")
+            await expect(composer().locator("textarea, input[name='nickname']")).toHaveCount(1);
+          else await expect(composer().locator("textarea, input[name='nickname']")).toHaveCount(0);
+          record(`${label}-${account}-gate`);
+        }
+        await setAccount(null);
+        await expect(composer().locator("textarea")).toHaveCount(0);
+        await expect(
+          row(comment.id).locator(':scope > .ryd-discussion-comment-actions [data-action="edit"]'),
+        ).toHaveCount(0);
+        for (const [value, expectedLike, expectedDislike] of [
+          [1, 1, 0],
+          [-1, 0, 1],
+          [-1, 0, 0],
+        ]) {
+          const reaction = row(comment.id).locator(
+            `:scope > .ryd-discussion-comment-actions [data-reaction="${value}"]`,
+          );
+          await expect(reaction).toBeEnabled();
+          await reaction.click();
+          await poll(
+            () => request(`/comments/${comment.id}`),
+            (item) => item.likes === expectedLike && item.dislikes === expectedDislike,
+            "Anonymous reaction count did not converge",
+          );
+          await expect(reaction).toBeEnabled();
+          await expect(reaction).toHaveAttribute(
+            "aria-pressed",
+            String((value === 1 ? expectedLike : expectedDislike) === 1),
+          );
+        }
+        record(`${label}-anonymous-like-dislike-remove`);
+
+        await setAccount("commenter");
+        await expect(composer().locator("textarea")).toHaveCount(1);
+        await expect(
+          row(comment.id).locator(':scope > .ryd-discussion-comment-actions [data-action="edit"]'),
+        ).toHaveCount(1);
+        await page.setViewportSize({ width: 390, height: 844 });
+        const box = await root().boundingBox();
+        assert.ok(box && box.x >= -1 && box.x + box.width <= 391, "Panel overflows narrow viewport");
+        await screenshot(`${label}-narrow`);
+        await page.setViewportSize({ width: 1200, height: 900 });
+        if (surface === "shorts") {
+          await root().locator("textarea").first().focus();
+          await page.keyboard.press("Escape");
+          await expect(page.locator("#ryd-discussion-drawer")).toBeHidden();
+          await expect(page.locator("#ryd-discussion-launcher")).toBeFocused();
+          await page.keyboard.press("Enter");
+          await expect(root()).toBeVisible();
+        }
+        record(`${label}-responsive-and-owner-restoration`);
+
+        await moderation(comment, label);
+        await notifications(comment, label, catalog);
+
+        await page.evaluate(() => window.__discussionFixture.setKids(true));
+        await expect(
+          page.locator("#ryd-discussion-panel, #ryd-discussion-launcher, #ryd-discussion-drawer"),
+        ).toHaveCount(0);
+        await page.evaluate(() => window.__discussionFixture.setKids(false));
+        if (surface === "shorts")
+          await expect(page.locator("#ryd-discussion-launcher")).toHaveAttribute("aria-expanded", "true");
+        await expect(root()).toHaveCount(1);
+        record(`${label}-positive-kids-excluded-unknown-restored`);
+
+        await open({ language, surface, videoId, disabled: false, kids: false, dark: true });
+        await page.waitForTimeout(300);
+        await expect(
+          page.locator("#ryd-discussion-panel, #ryd-discussion-launcher, #ryd-discussion-drawer"),
+        ).toHaveCount(0);
+        record(`${label}-native-enabled-excluded`);
+      }
+    }
+    assert.equal(errors.length, 0, "Fixture page had uncaught errors");
+    record("no-uncaught-fixture-page-errors");
+  } catch (error) {
+    failure = {
+      name: error.name,
+      message: String(error.message)
+        .replace(/(access_token|sessionToken|token)=[^&\s]+/gi, "$1=[redacted]")
+        .slice(0, 2500),
+    };
+    if (adapter.page)
+      await adapter.page
+        .screenshot({ path: path.join(outputDirectory, "failure.png"), timeout: TIMEOUT_MS })
+        .catch(() => {});
+  } finally {
+    for (const id of commentsToRestore) {
+      await request(`/moderation/comments/${id}`, {
+        account: "moderator",
+        method: "POST",
+        body: { hidden: false },
+      }).catch(() => errors.push({ name: "RestoreCommentError", commentId: id }));
+    }
+    for (const id of profilesToRestore) {
+      await request(`/moderation/profiles/${id}/suspension`, {
+        account: "moderator",
+        method: "POST",
+        body: { suspended: false },
+      }).catch(() => errors.push({ name: "RestoreProfileError", profileId: id }));
+    }
+    for (const { id, account } of created.reverse()) {
+      try {
+        await request(`/comments/${id}`, { account, method: "DELETE" });
+      } catch {
+        errors.push({ name: "CleanupError", commentId: id });
+      }
+    }
+    await bounded(() => adapter.close(), "Close disposable profile", 10000).catch(() =>
+      errors.push({ name: "BrowserCleanupError" }),
+    );
+    await bounded(() => apiServer.close(), "Close fixture server", TIMEOUT_MS).catch(() =>
+      errors.push({ name: "ServerCleanupError" }),
+    );
+    await fs.writeFile(
+      path.join(outputDirectory, "result.json"),
+      JSON.stringify(
+        {
+          kind: "hermetic-generated-artifact",
+          scope: notificationFocus ? "notifications-and-reconnect" : "discussion-smoke",
+          buildId: marker.buildId,
+          artifactDirectory,
+          results,
+          screenshots,
+          ledger,
+          errors,
+          failure: failure || null,
+          limitations: [
+            "Fixture YouTube pages, not live YouTube",
+            "Headless disposable Chromium profile",
+            "No live account OAuth",
+            "No live YouTube toasts or cross-tab notification deduplication scenario",
+            "Native Firefox and Safari not exercised",
+          ],
+        },
+        null,
+        2,
+      ),
+    );
+  }
+  assert.equal(failure, undefined, failure?.message);
+  assert.equal(errors.length, 0, "Smoke cleanup or diagnostics failed");
+  return {
+    kind: "hermetic-generated-artifact",
+    scope: notificationFocus ? "notifications-and-reconnect" : "discussion-smoke",
+    buildId: marker.buildId,
+    assertions: results.length,
+    outputDirectory,
+  };
+}
+
+if (require.main === module)
+  runHermeticDiscussionSmoke()
+    .then((result) => process.stdout.write(`${JSON.stringify(result)}\n`))
+    .catch((error) => {
+      process.stderr.write(`${error.message}\n`);
+      process.exitCode = 1;
+    });
+
+module.exports = { fixture, runHermeticDiscussionSmoke };
diff --git a/Extensions/e2e/discussion/live-discussion-contract.js b/Extensions/e2e/discussion/live-discussion-contract.js
new file mode 100644
index 0000000..d1b1061
--- /dev/null
+++ b/Extensions/e2e/discussion/live-discussion-contract.js
@@ -0,0 +1,1047 @@
+const assert = require("node:assert/strict");
+const crypto = require("node:crypto");
+const fs = require("node:fs/promises");
+const path = require("node:path");
+const TIMEOUT_MS = 5000;
+const DEFAULT_STAGES = [
+  "render",
+  "authoring",
+  "access",
+  "reactions",
+  "sorting",
+  "moderation",
+  "notifications",
+  "responsive",
+  "keyboard",
+  "cleanup",
+  "navigation",
+];
+
+function safeDiagnostic(value) {
+  return String(value)
+    .replace(/(access_token|sessionToken|token)=([^&\s]+)/gi, "$1=[redacted]")
+    .slice(0, 800);
+}
+
+async function bounded(work, label, timeout = TIMEOUT_MS) {
+  let timer;
+  try {
+    return await Promise.race([
+      Promise.resolve().then(work),
+      new Promise((_, reject) => {
+        timer = setTimeout(() => reject(new Error(`${label} exceeded ${timeout}ms`)), timeout);
+      }),
+    ]);
+  } finally {
+    clearTimeout(timer);
+  }
+}
+
+const DEFAULT_VIDEOS = {
+  watch: "6Rt2HtMsP6M",
+  shorts: "5QS-aIVIH9o",
+  enabled: "sYi2Sf_Bysg",
+};
+
+function localClient(origin, accounts, onResponse = () => {}) {
+  const url = new URL(origin);
+  assert.ok(["127.0.0.1", "localhost", "[::1]"].includes(url.hostname), "Mutation tests require loopback API");
+  assert.ok(
+    ["http:", "https:"].includes(url.protocol) && !url.username && !url.password,
+    "Invalid loopback API origin",
+  );
+  return async (route, { account, method = "GET", body, expected = 200 } = {}) => {
+    const token = account ? accounts[account]?.sessionToken || accounts[account]?.token : null;
+    if (account) assert.ok(token, `Missing local account: ${account}`);
+    const response = await fetch(`${url.origin}/api/discussion${route}`, {
+      method,
+      headers: { "Content-Type": "application/json", ...(token ? { Authorization: `Bearer ${token}` } : {}) },
+      body: body === undefined ? undefined : JSON.stringify(body),
+      signal: AbortSignal.timeout(TIMEOUT_MS),
+    });
+    const data = await response.json().catch(() => null);
+    onResponse({
+      source: "loopback-client",
+      method,
+      path: `/api/discussion${route.split("?")[0]}`,
+      status: response.status,
+    });
+    assert.equal(
+      response.status,
+      expected,
+      `${method} ${route.split("?")[0]} failed: ${data?.code || response.status}`,
+    );
+    return data;
+  };
+}
+
+function assertLocalRuntime(origin, runtime, health) {
+  localClient(origin, {});
+  assert.equal(health?.localTestMode, true, "Local discussion host marker is required");
+  assert.match(runtime?.buildId || "", /^[a-f0-9]{32}$/, "Generated live build marker is required");
+  assert.equal(runtime?.localOriginMatched, true, "Loaded extension must use the requested local discussion origin");
+  assert.equal(runtime?.localHostPermission, true, "Loaded extension is missing its local test host permission");
+  return { buildId: runtime.buildId, extensionId: runtime.extensionId, origin: new URL(origin).origin };
+}
+
+function createFixtureCleanup(request) {
+  const comments = new Map();
+  const pending = [];
+  const hidden = new Set();
+  const suspended = new Set();
+  const reports = new Set();
+  const remember = (comment, account) => {
+    if (comment?.id) {
+      comments.set(comment.id, { ...comment, account });
+      for (const fixture of pending)
+        if (
+          fixture.account === account &&
+          fixture.text === comment.text &&
+          (fixture.parentId || null) === (comment.parentId || null)
+        )
+          fixture.resolvedId = comment.id;
+    }
+    return comment;
+  };
+  return {
+    remember,
+    pending,
+    hidden,
+    suspended,
+    reports,
+    async run() {
+      const results = [];
+      async function attempt(name, work) {
+        try {
+          await bounded(work, name);
+          results.push({ name, passed: true });
+        } catch (error) {
+          results.push({ name, passed: false, message: safeDiagnostic(error.message) });
+        }
+      }
+      for (const id of hidden)
+        await attempt(`restore-comment:${id}`, () =>
+          request(`/moderation/comments/${id}`, { account: "moderator", method: "POST", body: { hidden: false } }),
+        );
+      for (const id of suspended)
+        await attempt(`restore-profile:${id}`, () =>
+          request(`/moderation/profiles/${id}/suspension`, {
+            account: "moderator",
+            method: "POST",
+            body: { suspended: false },
+          }),
+        );
+      for (const fixture of pending.filter((item) => !item.resolvedId))
+        await attempt(`discover-created:${fixture.label}`, async () => {
+          const route = fixture.parentId
+            ? `/comments/${fixture.parentId}/replies`
+            : `/videos/${fixture.videoId}/comments?sort=new`;
+          let cursor = null;
+          const deadline = Date.now() + TIMEOUT_MS;
+          do {
+            const data = await request(
+              `${route}${cursor ? `${route.includes("?") ? "&" : "?"}cursor=${encodeURIComponent(cursor)}` : ""}`,
+              { account: fixture.account },
+            );
+            const found = (data.items || []).filter((comment) => comment.text === fixture.text);
+            for (const comment of found) remember(comment, fixture.account);
+            if (found.length) break;
+            cursor = data.nextCursor;
+            if (cursor && Date.now() >= deadline) throw new Error("Fixture discovery exceeded its deadline");
+          } while (cursor);
+        });
+      for (const comment of [...comments.values()].sort((a, b) => Number(!!b.parentId) - Number(!!a.parentId)))
+        await attempt(`delete-created:${comment.id}`, async () => {
+          const current = await request(`/comments/${comment.id}`, { account: comment.account });
+          if (!current.deleted)
+            await request(`/comments/${comment.id}`, { account: comment.account, method: "DELETE" });
+          const verified = await request(`/comments/${comment.id}`, { account: comment.account });
+          assert.equal(verified.deleted, true, "Fixture deletion did not persist");
+          assert.equal(verified.text, "", "Fixture body remains public");
+        });
+      for (const id of reports)
+        await attempt(`dismiss-created:${id}`, () =>
+          request(`/moderation/reports/${id}/dismiss`, { account: "moderator", method: "POST", body: {} }),
+        );
+      return results;
+    },
+  };
+}
+
+function solve(challenge, difficulty) {
+  assert.ok(Number.isInteger(difficulty) && difficulty >= 0 && difficulty <= 24, "Invalid local puzzle difficulty");
+  const buffer = Buffer.alloc(20);
+  const decoded = Buffer.from(challenge, "base64");
+  assert.equal(decoded.length, 16, "Invalid local puzzle challenge");
+  decoded.copy(buffer, 4);
+  const deadline = Date.now() + TIMEOUT_MS;
+  for (let value = 0; value < 2 ** difficulty * 20; value++) {
+    if (value % 1024 === 0 && Date.now() >= deadline) throw new Error("Local puzzle exceeded 5000ms");
+    buffer.writeUInt32LE(value, 0);
+    const digest = crypto.createHash("sha512").update(buffer).digest();
+    let zeros = 0;
+    for (const byte of digest) {
+      if (byte === 0) zeros += 8;
+      else {
+        zeros += Math.clz32(byte) - 24;
+        break;
+      }
+    }
+    if (zeros >= difficulty) return buffer.subarray(0, 4).toString("base64");
+  }
+  throw new Error("Local reaction challenge exhausted");
+}
+
+async function poll(probe, accept, message, timeout = TIMEOUT_MS) {
+  const deadline = Date.now() + timeout;
+  let value;
+  while (Date.now() < deadline) {
+    value = await bounded(probe, message, Math.max(1, deadline - Date.now()));
+    if (accept(value)) return value;
+    await new Promise((resolve) => setTimeout(resolve, Math.min(150, Math.max(0, deadline - Date.now()))));
+  }
+  throw new Error(message);
+}
+
+/**
+ * Runs selected stages against the generated extension on native YouTube.
+ * Example: { surfaces: ["watch"], stages: ["authoring", "reactions"] }.
+ * A render-only stage does not create comments. Other stages seed missing prerequisites through the loopback API.
+ * The caller owns one persistent browser connection and switches YouTube UI language before each final run.
+ */
+async function runLiveDiscussionMatrix({
+  page,
+  popup,
+  setAccount,
+  accounts,
+  origin,
+  language,
+  outputDirectory,
+  videos = DEFAULT_VIDEOS,
+  surfaces = ["watch", "shorts"],
+  stages = DEFAULT_STAGES,
+  checkpoint = () => {},
+  notificationObserver,
+  captureScreenshot,
+}) {
+  assert.ok(["en", "ru"].includes(language));
+  assert.ok(surfaces.length && surfaces.every((value) => ["watch", "shorts"].includes(value)), "Invalid surfaces");
+  assert.ok(
+    stages.every((value) => DEFAULT_STAGES.includes(value)),
+    "Invalid stages",
+  );
+  const selected = new Set(stages.length ? stages : ["render"]);
+  page.setDefaultTimeout(TIMEOUT_MS);
+  page.setDefaultNavigationTimeout(TIMEOUT_MS);
+  popup.setDefaultTimeout(TIMEOUT_MS);
+  await fs.mkdir(outputDirectory, { recursive: true });
+  const results = [];
+  const diagnostics = [];
+  const ledger = [];
+  const request = localClient(origin, accounts, (entry) => ledger.push(entry));
+  const fixtures = createFixtureCleanup(request);
+  const cleanupResults = [];
+  const stageResults = [];
+  const omissions = [
+    ...DEFAULT_STAGES.filter((stage) => !selected.has(stage)).map((stage) => ({ stage, reason: "Not selected" })),
+    ...[
+      "native-language-menu",
+      "native-theme-switch",
+      "spa-and-recycled-shorts",
+      "explicit-native-kids",
+      "cross-tab-toasts",
+      "offline-and-worker-restart",
+      "cursor-pagination",
+    ].map((stage) => ({ stage, reason: "Caller-owned supplementary acceptance" })),
+    ...(!notificationObserver
+      ? [{ stage: "native-signalr-frames", reason: "No native socket observer supplied; runtime inbox delivery only" }]
+      : []),
+  ];
+  let runtime = null;
+  const responseListener = (response) => {
+    const url = new URL(response.url());
+    if (url.origin !== new URL(origin).origin || !url.pathname.startsWith("/api/discussion/")) return;
+    ledger.push({
+      source: "browser",
+      method: response.request().method(),
+      path: url.pathname,
+      status: response.status(),
+    });
+  };
+  const errorListener = (error) => diagnostics.push({ kind: "page", message: safeDiagnostic(error.message) });
+  page.context().on("response", responseListener);
+  page.on("pageerror", errorListener);
+  const record = (name, details = {}) => {
+    results.push({ name, passed: true, ...details });
+    checkpoint(name);
+  };
+  const message = (operation, payload = {}) =>
+    bounded(
+      () =>
+        popup.evaluate(
+          ({ operation, payload }) => chrome.runtime.sendMessage({ message: "ryd_discussion", operation, payload }),
+          { operation, payload },
+        ),
+      `Worker ${operation}`,
+    );
+  const root = () => page.locator("#ryd-discussion-panel, #ryd-discussion-drawer").filter({ visible: true });
+  const row = (id) => root().locator(`[data-comment-id="${id}"]`);
+  const actions = (id) => row(id).locator(":scope > .ryd-discussion-comment-actions");
+  const editor = (id) => row(id).locator(":scope > .ryd-discussion-inline-editor");
+  const profiles = new Map();
+  async function ensureProfile(name) {
+    let value = await request("/me", { account: name });
+    if (!value.profile?.nickname)
+      value = await request("/me/profile", {
+        account: name,
+        method: "PUT",
+        body: { nickname: `Test ${name} ${crypto.randomBytes(3).toString("hex")}` },
+      });
+    profiles.set(name, value.profile?.id);
+  }
+  const checkLocale = async () => assert.ok((await page.locator("html").getAttribute("lang")).startsWith(language));
+  async function account(name) {
+    if (name && !profiles.has(name)) await ensureProfile(name);
+    await bounded(() => setAccount(name), "Set local extension account");
+    await poll(
+      () => message("session"),
+      (response) =>
+        response.ok &&
+        (name == null
+          ? !response.data.authenticated
+          : response.data.authenticated && response.data.profile?.id === profiles.get(name)),
+      "Extension session did not converge",
+    );
+  }
+  async function open(surface) {
+    const deadline = Date.now() + 25000;
+    const remaining = () => Math.max(1, deadline - Date.now());
+    await bounded(
+      async () => {
+        await page.goto(
+          `https://www.youtube.com/${surface === "watch" ? `watch?v=${videos.watch}` : `shorts/${videos.shorts}`}`,
+          { waitUntil: "domcontentloaded", timeout: Math.min(TIMEOUT_MS, remaining()) },
+        );
+        await checkLocale();
+        const native = await poll(
+          () =>
+            bounded(
+              () =>
+                page.evaluate(
+                  ({ surface, videoId }) => {
+                    const data = (node) => node?.polymerController?.data || node?.data;
+                    if (surface === "shorts") {
+                      const player = document.querySelector("#shorts-player");
+                      let currentId;
+                      try {
+                        currentId = player?.getVideoData?.()?.video_id;
+                      } catch {
+                        return null;
+                      }
+                      const reel = player?.closest("ytd-reel-video-renderer");
+                      if (currentId !== videoId || !reel) return null;
+                      const buttons = [
+                        ...(data(reel.querySelector("reel-action-bar-view-model"))?.buttonViewModels || []),
+                        ...(data(reel)?.overlay?.reelPlayerOverlayRenderer?.buttonBar?.reelActionBarViewModel
+                          ?.buttonViewModels || []),
+                      ];
+                      return buttons.some(
+                        ({ buttonViewModel: button }) =>
+                          button?.iconName === "SHORTS_COMMENT" && button.state === "BUTTON_VIEW_MODEL_STATE_DISABLED",
+                      )
+                        ? { videoId, evidence: "current-shorts-disabled-action" }
+                        : null;
+                    }
+                    const watch = [...document.querySelectorAll("ytd-watch-flexy, ytd-watch-grid")].find(
+                      (node) => node.getAttribute("video-id") === videoId,
+                    );
+                    if (!watch) return null;
+                    const disabledLink = (value) => {
+                      try {
+                        const url = new URL(value, location.origin);
+                        return url.hostname === "support.google.com" && url.pathname === "/youtube/answer/9706180";
+                      } catch {
+                        return false;
+                      }
+                    };
+                    const hasNotice = (value, depth = 0) =>
+                      value &&
+                      typeof value === "object" &&
+                      depth <= 14 &&
+                      (value.messageRenderer?.text?.runs?.some((run) =>
+                        disabledLink(run.navigationEndpoint?.urlEndpoint?.url),
+                      ) ||
+                        Object.values(value).some((child) => hasNotice(child, depth + 1)));
+                    for (const comments of watch.querySelectorAll("ytd-comments")) {
+                      comments.scrollIntoView({ block: "center" });
+                      if (
+                        comments.getBoundingClientRect().height > 0 &&
+                        (hasNotice(data(comments)) ||
+                          [...comments.querySelectorAll("ytd-message-renderer a[href]")].some((anchor) =>
+                            disabledLink(anchor.href),
+                          ))
+                      )
+                        return { videoId, evidence: "native-disabled-comments-notice" };
+                    }
+                    return null;
+                  },
+                  { surface, videoId: videos[surface] },
+                ),
+              "Inspect native YouTube anchor",
+              Math.min(TIMEOUT_MS, remaining()),
+            ),
+          Boolean,
+          "Native YouTube disabled-comments anchor did not hydrate",
+          Math.min(20000, remaining()),
+        );
+        record(`${surface}:native-anchor-ready`, native);
+        checkpoint(`${surface}:ryd-panel-wait`);
+        await bounded(
+          async () => {
+            await poll(
+              () => page.locator("html").getAttribute("data-ryd-extension-build"),
+              (buildId) => buildId === runtime.buildId,
+              "Content runtime does not match the guarded live build",
+              Math.min(TIMEOUT_MS, remaining()),
+            );
+            if (surface === "shorts") {
+              await page
+                .locator("#ryd-discussion-launcher")
+                .waitFor({ state: "visible", timeout: Math.min(TIMEOUT_MS, remaining()) });
+              await page.locator("#ryd-discussion-launcher").click({ timeout: Math.min(TIMEOUT_MS, remaining()) });
+            }
+            await root().waitFor({ state: "visible", timeout: Math.min(TIMEOUT_MS, remaining()) });
+            assert.equal(await root().count(), 1);
+            assert.equal(await root().getAttribute("data-video-id"), videos[surface]);
+          },
+          "RYD panel readiness",
+          Math.min(TIMEOUT_MS, remaining()),
+        );
+        record(`${surface}:ryd-panel-ready`);
+      },
+      "Open native video and discussion",
+      25000,
+    );
+  }
+  async function capture(name) {
+    await poll(
+      () =>
+        root()
+          .evaluate((node) => {
+            node.scrollIntoView({ block: "center" });
+            return node.isConnected;
+          })
+          .catch((error) => {
+            if (/not attached|Execution context was destroyed/.test(error.message)) return false;
+            throw error;
+          }),
+      Boolean,
+      "The discussion container changed during screenshot preparation",
+    );
+    await bounded(
+      () =>
+        captureScreenshot
+          ? captureScreenshot(page, path.join(outputDirectory, `${name}.png`))
+          : page.screenshot({
+              path: path.join(outputDirectory, `${name}.png`),
+              animations: "disabled",
+              mask: [page.locator("#avatar-btn")],
+              timeout: TIMEOUT_MS,
+            }),
+      `Screenshot ${name}`,
+    );
+  }
+  async function newest(id) {
+    await root().locator(".ryd-discussion-thread > .ryd-discussion-toolbar select").selectOption("new");
+    await row(id).waitFor({ state: "visible", timeout: TIMEOUT_MS });
+  }
+  const inboxEvents = () =>
+    bounded(() => popup.evaluate(() => globalThis.__rydDiscussionLiveInboxEvents || []), "Read incoming inbox events");
+  let failure = null;
+  try {
+    const health = await request("/local/health");
+    const metadata = await bounded(
+      () =>
+        popup.evaluate(async (origin) => {
+          const manifest = chrome.runtime.getManifest();
+          const read = (name) => fetch(chrome.runtime.getURL(name), { signal: AbortSignal.timeout(5000) });
+          const [markerResponse, backgroundResponse] = await Promise.all([
+            read("live-build.json"),
+            read("ryd.background.js"),
+          ]);
+          const marker = markerResponse.ok ? await markerResponse.json() : null;
+          const background = backgroundResponse.ok ? await backgroundResponse.text() : "";
+          return {
+            extensionId: chrome.runtime.id,
+            buildId: marker?.buildId,
+            localOriginMatched: background.includes(`const testOrigin =  true ? ${JSON.stringify(origin)}`),
+            localHostPermission:
+              manifest.host_permissions?.some(
+                (pattern) =>
+                  pattern === `${origin}/*` || pattern === `${new URL(origin).protocol}//${new URL(origin).hostname}/*`,
+              ) === true,
+          };
+        }, new URL(origin).origin),
+      "Verify local extension runtime",
+    );
+    runtime = assertLocalRuntime(origin, metadata, health);
+    record("local-runtime-and-host-guard", runtime);
+    await bounded(
+      () =>
+        popup.evaluate(() => {
+          if (globalThis.__rydDiscussionLiveInboxListener)
+            chrome.runtime.onMessage.removeListener(globalThis.__rydDiscussionLiveInboxListener);
+          globalThis.__rydDiscussionLiveInboxEvents = [];
+          let sequence = 0;
+          globalThis.__rydDiscussionLiveInboxListener = (event) => {
+            if (event?.message !== "ryd_discussion_event" || event.type !== "inbox") return;
+            globalThis.__rydDiscussionLiveInboxEvents.push({
+              sequence: ++sequence,
+              data: {
+                unreadCount: event.data?.unreadCount,
+                revision: event.data?.revision,
+                items: (event.data?.items || []).map(({ id, commentId, type, read, revision }) => ({
+                  id,
+                  commentId,
+                  type,
+                  read,
+                  revision,
+                })),
+              },
+            });
+            if (globalThis.__rydDiscussionLiveInboxEvents.length > 100)
+              globalThis.__rydDiscussionLiveInboxEvents.shift();
+          };
+          chrome.runtime.onMessage.addListener(globalThis.__rydDiscussionLiveInboxListener);
+        }),
+      "Install incoming inbox observer",
+    );
+    for (const surface of surfaces) {
+      const videoId = videos[surface];
+      await account("commenter");
+      const session = await message("session");
+      if (!session.data.profile?.nickname) {
+        const result = await message("profile", {
+          nickname: `Test Commenter ${crypto.randomBytes(3).toString("hex")}`,
+        });
+        assert.equal(result.ok, true);
+      }
+      await open(surface);
+      const marker = `${language} ${surface} ${crypto.randomUUID()}`;
+      const text = `Local discussion check ${marker} <b>plain text</b>`;
+      const composer = root().locator(".ryd-discussion-composer textarea[name=comment]");
+      let comment;
+      if (selected.has("authoring")) {
+        const accountControls = root().locator(".ryd-discussion-composer .ryd-discussion-account button");
+        if (await accountControls.count()) await accountControls.click();
+        const nickname = `Live ${language} ${surface} ${crypto.randomBytes(3).toString("hex")}`;
+        await root().locator('.ryd-discussion-composer input[name="nickname"]').fill(nickname);
+        await root().locator('.ryd-discussion-composer button[type="submit"]').click();
+        await poll(
+          () => request("/me", { account: "commenter" }),
+          (data) => data.profile?.nickname === nickname,
+          "Nickname change did not persist",
+        );
+        await composer.waitFor({ state: "visible" });
+        record(`${surface}:nickname-ui-change`);
+        fixtures.pending.push({ label: `${surface}-root`, videoId, text, account: "commenter" });
+        await composer.fill(text);
+        await root().locator(".ryd-discussion-composer [data-action=post]").click();
+        const created = await poll(
+          () => request(`/videos/${videoId}/comments?sort=new`, { account: "commenter" }),
+          (result) => result.items.some((item) => item.text === text),
+          "Posted comment missing from authoritative list",
+        );
+        comment = fixtures.remember(
+          created.items.find((item) => item.text === text),
+          "commenter",
+        );
+        await newest(comment.id);
+        assert.equal(await row(comment.id).locator(".ryd-discussion-comment-text").first().textContent(), text);
+        assert.equal(await row(comment.id).locator(".ryd-discussion-comment-text b").count(), 0);
+        record(`${surface}:create-plain-text`);
+
+        await actions(comment.id).locator("[data-action=edit]").click();
+        await editor(comment.id).locator("textarea[name=comment]").fill(`Edited ${text}`);
+        await editor(comment.id).locator("[data-action=save]").click();
+        await poll(
+          () => request(`/comments/${comment.id}`, { account: "commenter" }),
+          (data) => data.text === `Edited ${text}`,
+          "Edit was not persisted",
+        );
+        record(`${surface}:edit`);
+
+        await actions(comment.id).locator("[data-action=reply]").click();
+        const replyText = `Reply ${marker}`;
+        fixtures.pending.push({
+          label: `${surface}-reply`,
+          videoId,
+          parentId: comment.id,
+          text: replyText,
+          account: "commenter",
+        });
+        await editor(comment.id).locator("textarea[name=comment]").fill(replyText);
+        await editor(comment.id).locator("[data-action=post]").click();
+        const replies = await poll(
+          () => request(`/comments/${comment.id}/replies`, { account: "commenter" }),
+          (data) => data.items.some((item) => item.text === replyText),
+          "Reply was not persisted",
+        );
+        fixtures.remember(
+          replies.items.find((item) => item.text === replyText),
+          "commenter",
+        );
+        record(`${surface}:reply`);
+        await capture(`${surface}-authoring`);
+      }
+      if (
+        !comment &&
+        ["access", "reactions", "sorting", "moderation", "notifications", "cleanup"].some((stage) =>
+          selected.has(stage),
+        )
+      ) {
+        fixtures.pending.push({ label: `${surface}-root`, videoId, text, account: "commenter" });
+        comment = await request(`/videos/${videoId}/comments`, {
+          account: "commenter",
+          method: "POST",
+          body: { text, requestId: crypto.randomUUID() },
+        });
+        fixtures.remember(comment, "commenter");
+        await newest(comment.id);
+        record(`${surface}:local-fixture`, { commentId: comment.id });
+      }
+      if (!stages.length || selected.has("render")) {
+        await capture(`${surface}-render`);
+        record(`${surface}:render`);
+      }
+      if (selected.has("access")) {
+        await account("premium");
+        await composer.waitFor({ state: "visible" });
+        assert.equal((await message("session")).data.canPost, true);
+        record(`${surface}:premium-posting-gate`);
+        for (const name of ["supporter", "inactive"]) {
+          await account(name);
+          await poll(
+            () => composer.count(),
+            (count) => count === 0,
+            `${name} account still has composer`,
+          );
+          assert.equal((await message("session")).data.canPost, false);
+          record(`${surface}:${name}-posting-gate`);
+        }
+        await account(null);
+        await newest(comment.id);
+        assert.equal(await composer.count(), 0);
+        await poll(
+          () => actions(comment.id).locator("[data-action=edit]").count(),
+          (count) => count === 0,
+          "Signed-out author actions remain",
+        );
+        record(`${surface}:signed-out-author-controls`);
+        await account("commenter");
+        await newest(comment.id);
+        await actions(comment.id).locator("[data-action=edit]").waitFor({ state: "visible" });
+        record(`${surface}:author-controls-restored`);
+      }
+      if (selected.has("reactions")) {
+        await account(null);
+        await newest(comment.id);
+        for (const value of [1, -1, -1]) {
+          const button = actions(comment.id).locator(`[data-reaction="${value}"]`);
+          await poll(() => button.isEnabled(), Boolean, "Reaction button not ready");
+          const expected = (await button.getAttribute("aria-pressed")) === "true" ? 0 : value;
+          const beforeValue =
+            (await actions(comment.id).locator('[data-reaction="1"]').getAttribute("aria-pressed")) === "true"
+              ? 1
+              : (await actions(comment.id).locator('[data-reaction="-1"]').getAttribute("aria-pressed")) === "true"
+                ? -1
+                : 0;
+          const before = await request(`/comments/${comment.id}`);
+          await button.click();
+          await poll(
+            async () => ({
+              enabled: await button.isEnabled(),
+              like: await actions(comment.id).locator('[data-reaction="1"]').getAttribute("aria-pressed"),
+              dislike: await actions(comment.id).locator('[data-reaction="-1"]').getAttribute("aria-pressed"),
+            }),
+            (state) =>
+              state.enabled && state.like === String(expected === 1) && state.dislike === String(expected === -1),
+            "Reaction did not match the requested transition",
+          );
+          const after = await request(`/comments/${comment.id}`);
+          assert.equal(after.likes, before.likes - Number(beforeValue === 1) + Number(expected === 1));
+          assert.equal(after.dislikes, before.dislikes - Number(beforeValue === -1) + Number(expected === -1));
+        }
+        assert.equal(await actions(comment.id).locator('[data-reaction="-1"]').getAttribute("aria-pressed"), "false");
+        record(`${surface}:anonymous-like-dislike-remove`);
+      }
+      if (selected.has("sorting")) {
+        for (const sort of ["new", "top"]) {
+          const expected = await request(`/videos/${videoId}/comments?sort=${sort}`);
+          await root().locator(".ryd-discussion-thread > .ryd-discussion-toolbar select").selectOption(sort);
+          await poll(
+            () =>
+              root()
+                .locator(".ryd-discussion-comments > [data-comment-id]")
+                .evaluateAll((nodes) => nodes.map((node) => node.dataset.commentId)),
+            (ids) => JSON.stringify(ids) === JSON.stringify(expected.items.map((item) => item.id)),
+            `Rendered ${sort} order differs from API`,
+          );
+        }
+        await newest(comment.id);
+        record(`${surface}:sorting`);
+      }
+      if (selected.has("moderation")) {
+        await ensureProfile("other");
+        await ensureProfile("moderator");
+        await account("other");
+        await newest(comment.id);
+        await actions(comment.id).locator("[data-action=report]").click();
+        await editor(comment.id).locator("[data-action=send-report]").click();
+        const submitted = await poll(
+          () => request("/moderation/reports", { account: "moderator" }),
+          (data) => data.items.some((item) => item.comment.id === comment.id),
+          "Report not persisted",
+        );
+        const reportId = submitted.items.find((item) => item.comment.id === comment.id).id;
+        fixtures.reports.add(reportId);
+        await account("moderator");
+        await root().locator("[data-action=moderation]").click();
+        const report = root().locator(`[data-report-id="${reportId}"]`);
+        await report.waitFor({ state: "visible" });
+        fixtures.hidden.add(comment.id);
+        await report.locator("[data-action=hide]").click();
+        await report.locator("[data-action=restore]").waitFor({ state: "visible" });
+        assert.equal((await request(`/comments/${comment.id}`)).hidden, true);
+        fixtures.suspended.add(comment.author.id);
+        await report.locator("[data-action=ban]").click();
+        await report.locator("[data-action=unban]").waitFor({ state: "visible" });
+        assert.equal((await request("/me", { account: "commenter" })).profile.suspended, true);
+        await report.locator("[data-action=dismiss]").click();
+        await report.waitFor({ state: "detached", timeout: TIMEOUT_MS });
+        fixtures.reports.delete(reportId);
+        await root().locator("[data-action=report-status]").selectOption("resolved");
+        await report.waitFor({ state: "visible" });
+        assert.ok(
+          (await request("/moderation/reports?status=resolved", { account: "moderator" })).items.some(
+            (item) => item.id === reportId,
+          ),
+        );
+        await capture(`${surface}-moderation-history`);
+        await report.locator("[data-action=restore]").click();
+        await report.locator("[data-action=hide]").waitFor({ state: "visible" });
+        assert.equal((await request(`/comments/${comment.id}`)).hidden, false);
+        fixtures.hidden.delete(comment.id);
+        await report.locator("[data-action=unban]").click();
+        await report.locator("[data-action=ban]").waitFor({ state: "visible" });
+        assert.equal((await request("/me", { account: "commenter" })).profile.suspended, false);
+        fixtures.suspended.delete(comment.author.id);
+        record(`${surface}:report-resolved-history-restore`);
+      }
+      if (selected.has("notifications")) {
+        await ensureProfile("other");
+        await account("commenter");
+        await root().locator("[data-action=discussion]").click();
+        const cleared = await message("readNotifications", { all: true });
+        assert.equal(cleared.ok, true);
+        for (const type of ["reply", "likes"]) {
+          const nativeBaseline = notificationObserver
+            ? await bounded(
+                () => notificationObserver.beforeActivity({ surface, type, commentId: comment.id }),
+                "Await native notification transport",
+              )
+            : null;
+          const baseline = (await inboxEvents()).at(-1)?.sequence || 0;
+          let activityId = comment.id;
+          if (type === "reply") {
+            const replyText = `Notification reply ${marker}`;
+            fixtures.pending.push({
+              label: `${surface}-notification-reply`,
+              videoId,
+              parentId: comment.id,
+              text: replyText,
+              account: "other",
+            });
+            const incomingReply = fixtures.remember(
+              await request(`/videos/${videoId}/comments`, {
+                account: "other",
+                method: "POST",
+                body: { text: replyText, parentId: comment.id, replyToId: comment.id, requestId: crypto.randomUUID() },
+              }),
+              "other",
+            );
+            activityId = incomingReply.id;
+          } else {
+            const userId = accounts.other.voterId;
+            assert.ok(userId, "Missing separate local reaction identity");
+            const challenge = await request(`/comments/${comment.id}/reaction/challenge`, {
+              method: "POST",
+              body: { userId, value: 1 },
+            });
+            await request(`/comments/${comment.id}/reaction/confirm`, {
+              method: "POST",
+              body: {
+                userId,
+                challengeId: challenge.challengeId,
+                solution: solve(challenge.challenge, challenge.difficulty),
+              },
+            });
+          }
+          if (notificationObserver) {
+            const proof = await bounded(
+              () =>
+                notificationObserver.afterActivity({ surface, type, commentId: activityId, baseline: nativeBaseline }),
+              "Await native incoming notification frame",
+            );
+            assert.equal(proof?.observed, true, "Native notification observer must attest a received frame");
+            record(`${surface}:${type}-native-signalr-frame`, {
+              revision: proof.revision == null ? null : String(proof.revision),
+              connection: Number.isInteger(proof.connection) ? proof.connection : null,
+            });
+          }
+          // Observe incoming delivery before explicitly reading the inbox or opening its UI.
+          const matches = (event) =>
+            event.sequence > baseline &&
+            event.data.items?.some((item) => item.commentId === activityId && item.type === type && !item.read);
+          const incomingEvents = await poll(
+            inboxEvents,
+            (events) => events.some(matches),
+            `Incoming runtime inbox event for ${type} did not arrive`,
+          );
+          const incoming = incomingEvents.find(matches);
+          const notification = incoming.data.items.find(
+            (item) => item.commentId === activityId && item.type === type && !item.read,
+          );
+          assert.ok(incoming.data.unreadCount > 0);
+          record(`${surface}:${type}-notification-runtime-event`, {
+            notificationId: notification.id,
+            revision: incoming.data.revision,
+          });
+          await root().locator("[data-action=inbox]").click();
+          const inboxRow = root().locator(`[data-notification-id="${notification.id}"]`);
+          await inboxRow.waitFor({ state: "visible" });
+          await capture(`${surface}-${type}-notifications`);
+          await inboxRow.locator("button").click();
+          await poll(
+            () => request("/notifications", { account: "commenter" }),
+            (data) => data.items.find((item) => item.id === notification.id)?.read === true,
+            "UI mark read was not persisted",
+          );
+          record(`${surface}:${type}-inbox-ui-mark-read`);
+          await root().locator("[data-action=discussion]").click();
+        }
+      }
+      if (selected.has("responsive")) {
+        const viewport = await bounded(
+          () => page.evaluate(() => ({ width: innerWidth, height: innerHeight })),
+          "Read original viewport",
+        );
+        try {
+          await bounded(() => page.setViewportSize({ width: 390, height: 844 }), "Set narrow viewport");
+          await poll(
+            () => root().boundingBox(),
+            (box) => box && box.x >= -1 && box.x + box.width <= 392,
+            "Discussion exceeds the narrow viewport",
+          );
+          await capture(`${surface}-390px`);
+          record(`${surface}:responsive-390px`);
+        } finally {
+          await bounded(() => page.setViewportSize(viewport), "Restore viewport");
+        }
+        let previousBox = null;
+        let stableSince = Date.now();
+        await poll(
+          async () => {
+            const box = JSON.stringify(await root().boundingBox());
+            if (box === "null" || box !== previousBox) stableSince = Date.now();
+            previousBox = box;
+            return Date.now() - stableSince >= 500;
+          },
+          Boolean,
+          "Discussion layout did not settle after restoring the viewport",
+        );
+      }
+      if (selected.has("keyboard")) {
+        await account("commenter");
+        await root().locator("[data-action=discussion]").click();
+        await composer.focus();
+        await bounded(() => page.keyboard.press("Tab"), "Keyboard Tab");
+        assert.ok(
+          await bounded(
+            () => root().evaluate((node) => node.contains(document.activeElement)),
+            "Inspect keyboard focus",
+          ),
+          "Keyboard Tab left the discussion panel",
+        );
+        if (surface === "shorts") {
+          const controls = root().locator(
+            "button:visible:not(:disabled), input:visible:not(:disabled), textarea:visible:not(:disabled), select:visible:not(:disabled), a[href]:visible",
+          );
+          await controls.last().focus();
+          await bounded(() => page.keyboard.press("Tab"), "Drawer focus wrap");
+          assert.ok(
+            await bounded(
+              () => controls.first().evaluate((node) => node === document.activeElement),
+              "Inspect wrapped focus",
+            ),
+            "Drawer keyboard focus did not wrap to its first control",
+          );
+          await bounded(() => page.keyboard.press("Escape"), "Close drawer with Escape");
+          await page.locator("#ryd-discussion-drawer").waitFor({ state: "hidden", timeout: TIMEOUT_MS });
+          assert.ok(
+            await bounded(
+              () => page.locator("#ryd-discussion-launcher").evaluate((node) => node === document.activeElement),
+              "Inspect launcher focus",
+            ),
+            "Closing the drawer did not return focus to its launcher",
+          );
+          await page.locator("#ryd-discussion-launcher").press("Enter");
+          await root().waitFor({ state: "visible", timeout: TIMEOUT_MS });
+        }
+        const keyboardText = `Keyboard submission ${marker}`;
+        fixtures.pending.push({ label: `${surface}-keyboard`, videoId, text: keyboardText, account: "commenter" });
+        await composer.fill(keyboardText);
+        await composer.press("Control+Enter");
+        const created = await poll(
+          () => request(`/videos/${videoId}/comments?sort=new`, { account: "commenter" }),
+          (data) => data.items.some((item) => item.text === keyboardText),
+          "Keyboard submission was not persisted",
+        );
+        const keyboardComment = fixtures.remember(
+          created.items.find((item) => item.text === keyboardText),
+          "commenter",
+        );
+        await capture(`${surface}-keyboard`);
+        await request(`/comments/${keyboardComment.id}`, { account: "commenter", method: "DELETE" });
+        record(`${surface}:keyboard-controls-and-submit`);
+      }
+      if (selected.has("cleanup") && comment) {
+        await account("commenter");
+        await root().locator("[data-action=discussion]").click();
+        await newest(comment.id);
+        const before = await request(`/comments/${comment.id}`);
+        await actions(comment.id).locator("[data-action=delete]").click();
+        await editor(comment.id).locator("[data-action=confirm-delete]").click();
+        const deleted = await poll(
+          () => request(`/comments/${comment.id}`),
+          (data) => data.deleted === true,
+          "Deleted comment did not become a tombstone",
+        );
+        assert.equal(deleted.text, "");
+        assert.equal(deleted.replyCount, before.replyCount);
+        record(`${surface}:delete-tombstone`);
+      }
+    }
+    if (selected.has("navigation")) {
+      await page.goto(`https://www.youtube.com/watch?v=${videos.enabled}`, { waitUntil: "domcontentloaded" });
+      await page.locator("ytd-comments").first().scrollIntoViewIfNeeded({ timeout: TIMEOUT_MS });
+      await page.locator("ytd-comments-header-renderer").first().waitFor({ state: "attached", timeout: TIMEOUT_MS });
+      assert.equal(await page.locator("#ryd-discussion-panel,#ryd-discussion-launcher").count(), 0);
+      record("enabled-video-excluded");
+      await page.goBack({ waitUntil: "domcontentloaded" });
+      const previous = surfaces.at(-1);
+      await page
+        .locator(previous === "shorts" ? "#ryd-discussion-launcher" : "#ryd-discussion-panel")
+        .waitFor({ state: "visible", timeout: TIMEOUT_MS });
+      record(`history-returns-to-${previous}`);
+    }
+    return {
+      language,
+      surfaces,
+      stages,
+      runtime,
+      results,
+      diagnostics,
+      ledger,
+      cleanupResults,
+      stageResults,
+      omissions,
+    };
+  } catch (error) {
+    failure = { message: safeDiagnostic(error.message) };
+    throw error;
+  } finally {
+    const completed = new Set(results.map((result) => result.name));
+    const lastCheck = {
+      render: "render",
+      authoring: "reply",
+      access: "author-controls-restored",
+      reactions: "anonymous-like-dislike-remove",
+      sorting: "sorting",
+      moderation: "report-resolved-history-restore",
+      notifications: "likes-inbox-ui-mark-read",
+      responsive: "responsive-390px",
+      keyboard: "keyboard-controls-and-submit",
+      cleanup: "delete-tombstone",
+    };
+    for (const surface of surfaces)
+      for (const [stage, check] of Object.entries(lastCheck))
+        stageResults.push({
+          surface,
+          stage,
+          status: !selected.has(stage)
+            ? "not-selected"
+            : completed.has(`${surface}:${check}`)
+              ? "passed"
+              : "not-completed",
+        });
+    stageResults.push({
+      stage: "navigation",
+      status: !selected.has("navigation")
+        ? "not-selected"
+        : completed.has(`history-returns-to-${surfaces.at(-1)}`)
+          ? "passed"
+          : "not-completed",
+    });
+    cleanupResults.push(...(await fixtures.run()));
+    const cleanupFailed = cleanupResults.some((result) => !result.passed);
+    if (cleanupFailed && !failure) failure = { message: "Local fixture cleanup failed; inspect cleanupResults" };
+    page.context().off("response", responseListener);
+    page.off("pageerror", errorListener);
+    await bounded(
+      () =>
+        popup.evaluate(() => {
+          if (globalThis.__rydDiscussionLiveInboxListener)
+            chrome.runtime.onMessage.removeListener(globalThis.__rydDiscussionLiveInboxListener);
+          delete globalThis.__rydDiscussionLiveInboxListener;
+          delete globalThis.__rydDiscussionLiveInboxEvents;
+        }),
+      "Remove incoming inbox observer",
+    ).catch(() => {});
+    await fs.writeFile(
+      path.join(outputDirectory, "results.json"),
+      JSON.stringify(
+        {
+          language,
+          surfaces,
+          stages,
+          runtime,
+          results,
+          diagnostics,
+          ledger,
+          cleanupResults,
+          stageResults,
+          omissions,
+          failure,
+        },
+        null,
+        2,
+      ),
+    );
+    if (cleanupFailed && failure?.message === "Local fixture cleanup failed; inspect cleanupResults")
+      throw new Error(failure.message);
+  }
+}
+
+module.exports = {
+  DEFAULT_VIDEOS,
+  DEFAULT_STAGES,
+  TIMEOUT_MS,
+  bounded,
+  assertLocalRuntime,
+  createFixtureCleanup,
+  localClient,
+  poll,
+  solve,
+  runLiveDiscussionMatrix,
+};
diff --git a/Extensions/e2e/discussion/live-discussion-contract.spec.js b/Extensions/e2e/discussion/live-discussion-contract.spec.js
new file mode 100644
index 0000000..807d0ed
--- /dev/null
+++ b/Extensions/e2e/discussion/live-discussion-contract.spec.js
@@ -0,0 +1,210 @@
+const crypto = require("node:crypto");
+const fs = require("node:fs/promises");
+const {
+  bounded,
+  localClient,
+  poll,
+  solve,
+  runLiveDiscussionMatrix,
+  assertLocalRuntime,
+  createFixtureCleanup,
+} = require("./live-discussion-contract");
+
+test("the mutation client rejects non-loopback origins before doing any work", () => {
+  expect(() => localClient("https://returnyoutubedislikeapi.com", {})).toThrow(/loopback/);
+  expect(() => localClient("http://name:password@127.0.0.1:5099", {})).toThrow(/Invalid loopback/);
+});
+
+test("a hanging probe cannot exceed the finite poll budget", async () => {
+  const started = Date.now();
+  await expect(poll(() => new Promise(() => {}), Boolean, "Probe stuck", 30)).rejects.toThrow(/exceeded/);
+  expect(Date.now() - started).toBeLessThan(1000);
+});
+
+test("bounded propagates real failures and clears its timeout after success", async () => {
+  await expect(bounded(() => 7, "Immediate", 30)).resolves.toBe(7);
+  await expect(
+    bounded(
+      () => {
+        throw new Error("Actual failure");
+      },
+      "Fail",
+      30,
+    ),
+  ).rejects.toThrow("Actual failure");
+});
+
+test("the local solver returns the four-byte SHA-512 proof format", () => {
+  const challenge = Buffer.alloc(16, 1).toString("base64");
+  const solution = Buffer.from(solve(challenge, 4), "base64");
+  expect(solution.length).toBe(4);
+  const digest = crypto
+    .createHash("sha512")
+    .update(Buffer.concat([solution, Buffer.from(challenge, "base64")]))
+    .digest();
+  expect(digest[0] >>> 4).toBe(0);
+  expect(() => solve(challenge, 99)).toThrow(/difficulty/);
+});
+
+test("staged runs reject invalid surfaces before touching a browser", async () => {
+  await expect(runLiveDiscussionMatrix({ language: "en", surfaces: ["mobile"], page: {}, popup: {} })).rejects.toThrow(
+    /Invalid surfaces/,
+  );
+  await expect(
+    runLiveDiscussionMatrix({ language: "en", surfaces: ["watch"], stages: ["unknown"], page: {}, popup: {} }),
+  ).rejects.toThrow(/Invalid stages/);
+});
+
+test("discussion create requests default to the implemented 200 response and ledger omits credentials", async () => {
+  const previousFetch = global.fetch;
+  const ledger = [];
+  global.fetch = jest.fn().mockResolvedValue({ status: 200, json: async () => ({ id: "created" }) });
+  try {
+    const request = localClient("http://127.0.0.1:5099", { writer: { sessionToken: "test-session" } }, (entry) =>
+      ledger.push(entry),
+    );
+    await expect(
+      request("/videos/abcdefghijk/comments", { account: "writer", method: "POST", body: { text: "Local text" } }),
+    ).resolves.toEqual({ id: "created" });
+    expect(global.fetch.mock.calls[0][0]).toBe("http://127.0.0.1:5099/api/discussion/videos/abcdefghijk/comments");
+    expect(JSON.stringify(ledger)).not.toContain("test-session");
+    expect(ledger).toEqual([
+      { source: "loopback-client", method: "POST", path: "/api/discussion/videos/abcdefghijk/comments", status: 200 },
+    ]);
+  } finally {
+    global.fetch = previousFetch;
+  }
+});
+
+test("the runtime guard requires both generated local artifact evidence and the local host marker", () => {
+  const runtime = {
+    buildId: "a".repeat(32),
+    extensionId: "fixture-extension",
+    localOriginMatched: true,
+    localHostPermission: true,
+  };
+  expect(assertLocalRuntime("http://127.0.0.1:5099", runtime, { localTestMode: true })).toEqual({
+    buildId: "a".repeat(32),
+    extensionId: "fixture-extension",
+    origin: "http://127.0.0.1:5099",
+  });
+  expect(() => assertLocalRuntime("https://example.com", runtime, { localTestMode: true })).toThrow(/loopback/);
+  expect(() => assertLocalRuntime("http://127.0.0.1:5099", runtime, {})).toThrow(/host marker/);
+  for (const override of [{ buildId: null }, { localOriginMatched: false }, { localHostPermission: false }])
+    expect(() =>
+      assertLocalRuntime("http://127.0.0.1:5099", { ...runtime, ...override }, { localTestMode: true }),
+    ).toThrow();
+});
+
+test("fixture cleanup restores moderation state and deletes replies before roots with their own authors", async () => {
+  const comments = new Map([
+    ["root", { id: "root", text: "Root", parentId: null, deleted: false }],
+    ["reply", { id: "reply", text: "Reply", parentId: "root", deleted: false }],
+  ]);
+  const request = jest.fn(async (route, options = {}) => {
+    const id = route.split("/").at(-1);
+    if (route.startsWith("/comments/")) {
+      if (options.method === "DELETE") comments.set(id, { ...comments.get(id), text: "", deleted: true });
+      return comments.get(id);
+    }
+    return {};
+  });
+  const cleanup = createFixtureCleanup(request);
+  cleanup.remember(comments.get("root"), "commenter");
+  cleanup.remember(comments.get("reply"), "other");
+  cleanup.hidden.add("root");
+  cleanup.suspended.add("author");
+  const results = await cleanup.run();
+  expect(results.every((value) => value.passed)).toBe(true);
+  expect(request.mock.calls.slice(0, 2).map(([route]) => route)).toEqual([
+    "/moderation/comments/root",
+    "/moderation/profiles/author/suspension",
+  ]);
+  expect(
+    request.mock.calls
+      .filter(([, options]) => options.method === "DELETE")
+      .map(([route, options]) => [route, options.account]),
+  ).toEqual([
+    ["/comments/reply", "other"],
+    ["/comments/root", "commenter"],
+  ]);
+});
+
+test("fixture cleanup discovers a committed UI post whose response was lost, without deleting unrelated rows", async () => {
+  const created = { id: "lost-response", text: "Unique attempt marker", deleted: false };
+  const request = jest.fn(async (route, options = {}) => {
+    if (route.startsWith("/videos/")) return { items: [created, { id: "unrelated", text: "Someone else" }] };
+    if (options.method === "DELETE") Object.assign(created, { deleted: true, text: "" });
+    return created;
+  });
+  const cleanup = createFixtureCleanup(request);
+  cleanup.pending.push({ label: "pending-root", videoId: "abcdefghijk", text: created.text, account: "commenter" });
+  expect((await cleanup.run()).every((value) => value.passed)).toBe(true);
+  expect(request.mock.calls.filter(([, options]) => options.method === "DELETE").map(([route]) => route)).toEqual([
+    "/comments/lost-response",
+  ]);
+});
+
+test("fixture cleanup reports a failed deletion and still attempts the remaining comments", async () => {
+  const deleted = new Set();
+  const request = jest.fn(async (route, options = {}) => {
+    const id = route.split("/").at(-1);
+    if (id === "bad") throw new Error("Local failure");
+    if (options.method === "DELETE") deleted.add(id);
+    return { id, deleted: deleted.has(id), text: deleted.has(id) ? "" : "Body" };
+  });
+  const cleanup = createFixtureCleanup(request);
+  cleanup.remember({ id: "bad" }, "commenter");
+  cleanup.remember({ id: "good" }, "commenter");
+  const results = await cleanup.run();
+  expect(results.find((item) => item.name === "delete-created:bad").passed).toBe(false);
+  expect(results.find((item) => item.name === "delete-created:good").passed).toBe(true);
+});
+
+test("a rejected runtime guard cannot switch accounts or make a mutation request", async () => {
+  const previousFetch = global.fetch;
+  const mkdir = jest.spyOn(fs, "mkdir").mockResolvedValue(undefined);
+  const writeFile = jest.spyOn(fs, "writeFile").mockResolvedValue(undefined);
+  global.fetch = jest.fn().mockResolvedValue({ status: 200, json: async () => ({ localTestMode: true }) });
+  const context = { on: jest.fn(), off: jest.fn() };
+  const page = {
+    setDefaultTimeout: jest.fn(),
+    setDefaultNavigationTimeout: jest.fn(),
+    context: () => context,
+    on: jest.fn(),
+    off: jest.fn(),
+  };
+  const popup = {
+    setDefaultTimeout: jest.fn(),
+    evaluate: jest
+      .fn()
+      .mockResolvedValue({ buildId: "a".repeat(32), localOriginMatched: false, localHostPermission: true }),
+  };
+  const setAccount = jest.fn();
+  try {
+    await expect(
+      runLiveDiscussionMatrix({
+        page,
+        popup,
+        setAccount,
+        accounts: {},
+        origin: "http://127.0.0.1:5099",
+        language: "en",
+        outputDirectory: "unused",
+        stages: ["authoring"],
+      }),
+    ).rejects.toThrow(/requested local discussion origin/);
+    expect(setAccount).not.toHaveBeenCalled();
+    expect(global.fetch).toHaveBeenCalledTimes(1);
+    expect(global.fetch.mock.calls[0][1].method).toBe("GET");
+    const receipt = JSON.parse(writeFile.mock.calls[0][1]);
+    expect(receipt.cleanupResults).toEqual([]);
+    expect(receipt.stageResults.find((value) => value.surface === "watch" && value.stage === "authoring").status).toBe(
+      "not-completed",
+    );
+  } finally {
+    global.fetch = previousFetch;
+    mkdir.mockRestore();
+    writeFile.mockRestore();
+  }
+});
diff --git a/Extensions/e2e/discussion/watch-width-smoke.js b/Extensions/e2e/discussion/watch-width-smoke.js
new file mode 100644
index 0000000..f32d52c
--- /dev/null
+++ b/Extensions/e2e/discussion/watch-width-smoke.js
@@ -0,0 +1,87 @@
+const assert = require("node:assert/strict");
+const fs = require("node:fs/promises");
+const path = require("node:path");
+const { chromium } = require("@playwright/test");
+
+async function runWatchWidthSmoke() {
+  const repository = path.resolve(__dirname, "../../..");
+  const output = path.join(repository, "test-results/discussion", `watch-width-${Date.now()}`);
+  const css = await fs.readFile(path.join(repository, "Extensions/combined/content-style.css"), "utf8");
+  await fs.mkdir(output, { recursive: true });
+  const browser = await chromium.launch({ headless: true });
+  const results = [];
+  try {
+    const context = await browser.newContext({ viewport: { width: 390, height: 844 } });
+    await context.route("**/*", (route) => route.abort());
+    const page = await context.newPage();
+    page.setDefaultTimeout(5000);
+    for (const language of ["en", "ru"]) {
+      const ru = language === "ru";
+      await page.setViewportSize({ width: 390, height: 844 });
+      await page.setContent(
+        `<!doctype html><html lang="${language}" dark><head><meta charset="utf-8"><style>
+        body{margin:0;padding:24px;display:flex;justify-content:center;font:14px Arial,sans-serif;background:#0f0f0f;color:#f1f1f1}
+        #native-parent{width:426.666px;min-width:426.666px;flex-shrink:0}
+        #native-comments{height:52px} ${css}
+      </style></head><body><main id="native-parent"><div id="native-comments">${ru ? "Комментарии отключены." : "Comments are turned off."}</div>
+        <section id="ryd-discussion-panel" class="ryd-discussion">
+          <header class="ryd-discussion-header"><div class="ryd-discussion-brand"><span class="ryd-discussion-logo">RYD</span><h2 class="ryd-discussion-title">${ru ? "Комментарии RYD" : "RYD comments"}</h2></div>
+          <nav class="ryd-discussion-header-actions"><button class="ryd-discussion-button">${ru ? "Обсуждение" : "Discussion"}</button><button class="ryd-discussion-button">${ru ? "Уведомления" : "Notifications"}</button><button class="ryd-discussion-button">${ru ? "Модерация" : "Moderation"}</button></nav></header>
+          <p class="ryd-discussion-description">${ru ? "Обсуждение сообщества Return YouTube Dislike." : "A community discussion hosted by Return YouTube Dislike."}</p>
+          <p class="ryd-discussion-independent">${ru ? "Эти комментарии не связаны с комментариями YouTube." : "These comments are separate from YouTube."}</p>
+          <textarea class="ryd-discussion-textarea">${ru ? "Проверка ширины комментариев" : "Discussion width check"}</textarea>
+          <div class="ryd-discussion-form-actions"><button class="ryd-discussion-button ryd-discussion-primary">${ru ? "Отправить" : "Post"}</button></div>
+        </section></main></body></html>`,
+        { timeout: 5000 },
+      );
+      const panel = page.locator("#ryd-discussion-panel");
+      const geometry = () =>
+        page.evaluate(() => {
+          const rect = document.querySelector("#ryd-discussion-panel").getBoundingClientRect();
+          return {
+            x: rect.x,
+            width: rect.width,
+            right: rect.right,
+            viewport: innerWidth,
+            nativeWidth: document.querySelector("#native-parent").getBoundingClientRect().width,
+          };
+        });
+      const oldSizing = await page.addStyleTag({ content: "#ryd-discussion-panel{max-inline-size:none}" });
+      await panel.scrollIntoViewIfNeeded();
+      const before = await geometry();
+      assert.ok(
+        before.x < 0 || before.right > before.viewport,
+        "The native wide parent must reproduce the original overflow",
+      );
+      await page.screenshot({ path: path.join(output, `${language}-before.png`), timeout: 5000 });
+      await oldSizing.evaluate((node) => node.remove());
+      await panel.scrollIntoViewIfNeeded();
+      const after = await geometry();
+      assert.equal(after.width, 342);
+      assert.ok(after.x >= 0 && after.right <= after.viewport, "The narrow watch panel must fit inside the viewport");
+      assert.equal(after.nativeWidth, before.nativeWidth, "Native container geometry must remain unchanged");
+      await page.screenshot({ path: path.join(output, `${language}-after.png`), timeout: 5000 });
+      await page.setViewportSize({ width: 1536, height: 639 });
+      const desktop = await geometry();
+      assert.equal(desktop.width, desktop.nativeWidth, "Desktop watch panel must still fill its parent");
+      results.push({ language, before, after, desktop, passed: true });
+    }
+    await fs.writeFile(
+      path.join(output, "result.json"),
+      JSON.stringify({ kind: "hermetic-css-layout", results }, null, 2),
+    );
+    return { output, results };
+  } finally {
+    await browser.close();
+  }
+}
+
+if (require.main === module)
+  runWatchWidthSmoke()
+    .then((result) => process.stdout.write(`${JSON.stringify(result)}\n`))
+    .catch((error) => {
+      process.stderr.write(`${error.message}\n`);
+      process.exitCode = 1;
+    });
+
+module.exports = { runWatchWidthSmoke };
diff --git a/Extensions/e2e/hermetic-api-contract.js b/Extensions/e2e/hermetic-api-contract.js
index ac4e0ee..04a004b 100644
--- a/Extensions/e2e/hermetic-api-contract.js
+++ b/Extensions/e2e/hermetic-api-contract.js
@@ -1,6 +1,7 @@
 const assert = require("node:assert/strict");
 
 const API_METHODS_BY_PATH = Object.freeze({
+  "/api/discussion/capabilities": Object.freeze(["GET"]),
   "/configs/selectors": Object.freeze(["GET"]),
   "/interact/confirmVote": Object.freeze(["POST"]),
   "/interact/vote": Object.freeze(["POST"]),
diff --git a/Extensions/e2e/hermetic-artifact-smoke.js b/Extensions/e2e/hermetic-artifact-smoke.js
index 717ed5e..f7ca855 100644
--- a/Extensions/e2e/hermetic-artifact-smoke.js
+++ b/Extensions/e2e/hermetic-artifact-smoke.js
@@ -619,6 +619,8 @@ async function startHermeticApiServer({ dislikes = 25, likes = 100 } = {}) {
     }
     let defaultBody;
     if (request.method === "GET" && url.pathname === "/configs/selectors") defaultBody = {};
+    else if (request.method === "GET" && url.pathname === "/api/discussion/capabilities")
+      defaultBody = { enabled: false };
     else if (request.method === "GET" && url.pathname === "/votes") {
       defaultBody = { dislikes, likes, rating: 4.5 };
     } else if (request.method === "GET" && url.pathname === "/puzzle/registration") {
diff --git a/Extensions/e2e/hermetic-artifact-smoke.spec.js b/Extensions/e2e/hermetic-artifact-smoke.spec.js
index 2b1978c..abc45dc 100644
--- a/Extensions/e2e/hermetic-artifact-smoke.spec.js
+++ b/Extensions/e2e/hermetic-artifact-smoke.spec.js
@@ -277,6 +277,21 @@ test("the loopback backend records and rejects an OPTIONS request to an unknown
   }
 });
 
+test("legacy artifact fixtures explicitly disable discussion and still reject discussion writes", async () => {
+  const apiServer = await startHermeticApiServer();
+  try {
+    const capabilities = await fetch(`${apiServer.origin}/api/discussion/capabilities`);
+    expect(capabilities.status).toBe(200);
+    expect(await capabilities.json()).toEqual({ enabled: false });
+    expect(apiServer.unexpectedRequests).toHaveLength(0);
+    const mutation = await fetch(`${apiServer.origin}/api/discussion/videos/abcdefghijk/comments`, { method: "POST" });
+    expect(mutation.status).toBe(404);
+    expect(apiServer.unexpectedRequests).toHaveLength(1);
+  } finally {
+    await apiServer.close();
+  }
+});
+
 function createPreflightRoute(pathname, requestedMethod) {
   const request = {
     headers: () => ({ "access-control-request-method": requestedMethod }),
diff --git a/package-lock.json b/package-lock.json
index efe2f73..5601771 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -12,6 +12,7 @@
         "npm": "10.8.2"
       },
       "dependencies": {
+        "@microsoft/signalr": "9.0.6",
         "country-code-lookup": "^0.1.3",
         "echarts": "^5.5.0",
         "topojson-client": "^3.1.0",
@@ -2502,6 +2503,40 @@
         "@jridgewell/sourcemap-codec": "^1.4.14"
       }
     },
+    "node_modules/@microsoft/signalr": {
+      "version": "9.0.6",
+      "resolved": "https://registry.npmjs.org/@microsoft/signalr/-/signalr-9.0.6.tgz",
+      "integrity": "sha512-DrhgzFWI9JE4RPTsHYRxh4yr+OhnwKz8bnJe7eIi7mLLjqhJpEb62CiUy/YbFvLqLzcGzlzz1QWgVAW0zyipMQ==",
+      "license": "MIT",
+      "dependencies": {
+        "abort-controller": "^3.0.0",
+        "eventsource": "^2.0.2",
+        "fetch-cookie": "^2.0.3",
+        "node-fetch": "^2.6.7",
+        "ws": "^7.5.10"
+      }
+    },
+    "node_modules/@microsoft/signalr/node_modules/ws": {
+      "version": "7.5.13",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-7.5.13.tgz",
+      "integrity": "sha512-rsKI6xDBFVf4r/x8XyChGK04QR/XHroxs/jUcoWvtEZM8TPU/X/uIY9B1CsSzYws9ZJb/6bbBu7dPhFW00CAoA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=8.3.0"
+      },
+      "peerDependencies": {
+        "bufferutil": "^4.0.1",
+        "utf-8-validate": "^5.0.2"
+      },
+      "peerDependenciesMeta": {
+        "bufferutil": {
+          "optional": true
+        },
+        "utf-8-validate": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/@nodelib/fs.scandir": {
       "version": "2.1.5",
       "dev": true,
@@ -2985,7 +3020,6 @@
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/abort-controller/-/abort-controller-3.0.0.tgz",
       "integrity": "sha512-h8lQ8tacZYnR3vNQTgibj+tODHI5/+l06Au2Pcriv/Gmet0eaj4TwWH41sO9wnHDiQsEj19q0drzdWdeAHtweg==",
-      "dev": true,
       "license": "MIT",
       "dependencies": {
         "event-target-shim": "^5.0.0"
@@ -4296,7 +4330,6 @@
       "version": "5.0.1",
       "resolved": "https://registry.npmjs.org/event-target-shim/-/event-target-shim-5.0.1.tgz",
       "integrity": "sha512-i/2XbnSz/uxRCU6+NdVJgKWDTM427+MqYbkQzD321DuCQJUqOuJKIA0IM2+W2xtYHdKOmZ4dR6fExsd4SXL+WQ==",
-      "dev": true,
       "license": "MIT",
       "engines": {
         "node": ">=6"
@@ -4317,6 +4350,15 @@
         "node": ">=0.8.x"
       }
     },
+    "node_modules/eventsource": {
+      "version": "2.0.2",
+      "resolved": "https://registry.npmjs.org/eventsource/-/eventsource-2.0.2.tgz",
+      "integrity": "sha512-IzUmBGPR3+oUG9dUeXynyNmf91/3zUSJg1lCktzKw47OXuhco54U3r9B7O4XX+Rb1Itm9OZ2b0RkTs10bICOxA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=12.0.0"
+      }
+    },
     "node_modules/execa": {
       "version": "5.1.1",
       "dev": true,
@@ -4427,6 +4469,40 @@
         "bser": "2.1.1"
       }
     },
+    "node_modules/fetch-cookie": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/fetch-cookie/-/fetch-cookie-2.2.0.tgz",
+      "integrity": "sha512-h9AgfjURuCgA2+2ISl8GbavpUdR+WGAM2McW/ovn4tVccegp8ZqCKWSBR8uRdM8dDNlx5WdKRWxBYUwteLDCNQ==",
+      "license": "Unlicense",
+      "dependencies": {
+        "set-cookie-parser": "^2.4.8",
+        "tough-cookie": "^4.0.0"
+      }
+    },
+    "node_modules/fetch-cookie/node_modules/tough-cookie": {
+      "version": "4.1.4",
+      "resolved": "https://registry.npmjs.org/tough-cookie/-/tough-cookie-4.1.4.tgz",
+      "integrity": "sha512-Loo5UUvLD9ScZ6jh8beX1T6sO1w2/MpCRpEP7V280GKMVUQ0Jzar2U3UJPsrdbziLEMMhu3Ujnq//rhiFuIeag==",
+      "license": "BSD-3-Clause",
+      "dependencies": {
+        "psl": "^1.1.33",
+        "punycode": "^2.1.1",
+        "universalify": "^0.2.0",
+        "url-parse": "^1.5.3"
+      },
+      "engines": {
+        "node": ">=6"
+      }
+    },
+    "node_modules/fetch-cookie/node_modules/universalify": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/universalify/-/universalify-0.2.0.tgz",
+      "integrity": "sha512-CJ1QgKmNg3CwvAv/kOFmtnEN05f0D/cn9QntgNOQlQF9dgvVTHj3t+8JPdjqawCHk7V/KA+fbUqzZ9XWhcqPUg==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 4.0.0"
+      }
+    },
     "node_modules/filemanager-webpack-plugin": {
       "version": "9.0.1",
       "resolved": "https://registry.npmjs.org/filemanager-webpack-plugin/-/filemanager-webpack-plugin-9.0.1.tgz",
@@ -6437,6 +6513,48 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/node-fetch": {
+      "version": "2.7.0",
+      "resolved": "https://registry.npmjs.org/node-fetch/-/node-fetch-2.7.0.tgz",
+      "integrity": "sha512-c4FRfUm/dbcWZ7U+1Wq0AwCyFL+3nt2bEw05wfxSz+DWpWsitgmSgYmy2dQdWyKC1694ELPqMs/YzUSNozLt8A==",
+      "license": "MIT",
+      "dependencies": {
+        "whatwg-url": "^5.0.0"
+      },
+      "engines": {
+        "node": "4.x || >=6.0.0"
+      },
+      "peerDependencies": {
+        "encoding": "^0.1.0"
+      },
+      "peerDependenciesMeta": {
+        "encoding": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/node-fetch/node_modules/tr46": {
+      "version": "0.0.3",
+      "resolved": "https://registry.npmjs.org/tr46/-/tr46-0.0.3.tgz",
+      "integrity": "sha512-N3WMsuqV66lT30CrXNbEjx4GEwlow3v6rr4mCcv6prnfwhS01rkgyFdjPNBYd9br7LpXV1+Emh01fHnq2Gdgrw==",
+      "license": "MIT"
+    },
+    "node_modules/node-fetch/node_modules/webidl-conversions": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/webidl-conversions/-/webidl-conversions-3.0.1.tgz",
+      "integrity": "sha512-2JAn3z8AR6rjK8Sm8orRC0h/bcl/DqL7tRPdGZ4I1CjdF+EaMLmYxBHyXuKL849eucPFhvBoxMsflfOb8kxaeQ==",
+      "license": "BSD-2-Clause"
+    },
+    "node_modules/node-fetch/node_modules/whatwg-url": {
+      "version": "5.0.0",
+      "resolved": "https://registry.npmjs.org/whatwg-url/-/whatwg-url-5.0.0.tgz",
+      "integrity": "sha512-saE57nupxk6v3HY35+jzBwYa0rKSy0XR8JSxZPwgLr7ys0IBzhGviA1/TUGJLmSVqs8pb9AnvICXEuOHLprYTw==",
+      "license": "MIT",
+      "dependencies": {
+        "tr46": "~0.0.3",
+        "webidl-conversions": "^3.0.0"
+      }
+    },
     "node_modules/node-int64": {
       "version": "0.4.0",
       "dev": true,
@@ -6802,16 +6920,33 @@
         "node": ">= 6"
       }
     },
+    "node_modules/psl": {
+      "version": "1.15.0",
+      "resolved": "https://registry.npmjs.org/psl/-/psl-1.15.0.tgz",
+      "integrity": "sha512-JZd3gMVBAVQkSs6HdNZo9Sdo0LNcQeMNP3CozBJb3JYC/QUYZTnKxP+f8oWRX4rHP5EurWxqAHTSwUCjlNKa1w==",
+      "license": "MIT",
+      "dependencies": {
+        "punycode": "^2.3.1"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/lupomontero"
+      }
+    },
     "node_modules/punycode": {
       "version": "2.3.1",
       "resolved": "https://registry.npmjs.org/punycode/-/punycode-2.3.1.tgz",
       "integrity": "sha512-vYt7UD1U9Wg6138shLtLOvdAu+8DsC/ilFtEVHcH+wydcSpNE20AfSOduf6MkRFahL5FY7X1oU7nKVZFtfq8Fg==",
-      "dev": true,
       "license": "MIT",
       "engines": {
         "node": ">=6"
       }
     },
+    "node_modules/querystringify": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/querystringify/-/querystringify-2.2.0.tgz",
+      "integrity": "sha512-FIqgj2EUvTa7R50u0rGsyTftzjYmv/a3hO345bZNrqabNqjtgiDMgmo4mkUjd+nzU5oF3dClKqFIPUKybUyqoQ==",
+      "license": "MIT"
+    },
     "node_modules/queue-microtask": {
       "version": "1.2.3",
       "dev": true,
@@ -6977,6 +7112,12 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/requires-port": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/requires-port/-/requires-port-1.0.0.tgz",
+      "integrity": "sha512-KigOCHcocU3XODJxsu8i/j8T9tzT4adHiecwORRQ0ZZFcp7ahwXuRU1m+yuO90C5ZUyGeGfocHDI14M3L3yDAQ==",
+      "license": "MIT"
+    },
     "node_modules/resolve": {
       "version": "1.20.0",
       "dev": true,
@@ -7214,6 +7355,12 @@
         "randombytes": "^2.1.0"
       }
     },
+    "node_modules/set-cookie-parser": {
+      "version": "2.7.2",
+      "resolved": "https://registry.npmjs.org/set-cookie-parser/-/set-cookie-parser-2.7.2.tgz",
+      "integrity": "sha512-oeM1lpU/UvhTxw+g3cIfxXHyJRc/uidd3yK1P242gzHds0udQBYzs3y8j4gCCW+ZJ7ad0yctld8RYO+bdurlvw==",
+      "license": "MIT"
+    },
     "node_modules/shallow-clone": {
       "version": "3.0.1",
       "resolved": "https://registry.npmjs.org/shallow-clone/-/shallow-clone-3.0.1.tgz",
@@ -7890,6 +8037,16 @@
         "punycode": "^2.1.0"
       }
     },
+    "node_modules/url-parse": {
+      "version": "1.5.10",
+      "resolved": "https://registry.npmjs.org/url-parse/-/url-parse-1.5.10.tgz",
+      "integrity": "sha512-WypcfiRhfeUP9vvF0j6rw0J3hrWrw6iZv3+22h6iRMJ/8z1Tj6XfLP4DsUix5MhMPnXpiHDoKyoZ/bdCkwBCiQ==",
+      "license": "MIT",
+      "dependencies": {
+        "querystringify": "^2.1.1",
+        "requires-port": "^1.0.0"
+      }
+    },
     "node_modules/us-atlas": {
       "version": "3.0.1",
       "resolved": "https://registry.npmjs.org/us-atlas/-/us-atlas-3.0.1.tgz",
diff --git a/package.json b/package.json
index 5b0df50..89160e5 100644
--- a/package.json
+++ b/package.json
@@ -53,6 +53,7 @@
   },
   "homepage": "https://github.com/Anarios/return-youtube-dislike#readme",
   "dependencies": {
+    "@microsoft/signalr": "9.0.6",
     "country-code-lookup": "^0.1.3",
     "echarts": "^5.5.0",
     "topojson-client": "^3.1.0",
diff --git a/webpack.config.js b/webpack.config.js
index 6975a51..c7d5935 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -20,7 +20,7 @@ const ignorePatterns = [
   ...entries.map((entry) => `**/${entry}.js`),
 ];
 
-const manifestTransform = (content, filename) => {
+const manifestTransform = (content, filename, discussionTestOrigin = "") => {
   const filteredContent = content
     .toString()
     .split("\n")
@@ -29,6 +29,12 @@ const manifestTransform = (content, filename) => {
 
   const manifestData = JSON.parse(filteredContent);
   manifestData.version = extensionVersion;
+  if (discussionTestOrigin) {
+    const testUrl = new URL(discussionTestOrigin);
+    const permission = `${testUrl.protocol}//${testUrl.hostname}/*`;
+    const permissionField = manifestData.manifest_version === 3 ? "host_permissions" : "permissions";
+    manifestData[permissionField] = [...new Set([...(manifestData[permissionField] || []), permission])];
+  }
   return JSON.stringify(manifestData, null, 2);
 };
 
@@ -103,6 +109,22 @@ class ExtensionBuildReceiptPlugin {
 
 module.exports = (env = {}, argv = {}) => {
   const liveTestBuild = env.liveTest === true || env.liveTest === "true";
+  let discussionTestOrigin = "";
+  if (env.discussionTestOrigin) {
+    if (!liveTestBuild) throw new Error("A local discussion origin requires the explicit live-test build.");
+    const origin = new URL(env.discussionTestOrigin);
+    if (
+      !["http:", "https:"].includes(origin.protocol) ||
+      !["127.0.0.1", "localhost", "[::1]"].includes(origin.hostname) ||
+      origin.username ||
+      origin.password ||
+      origin.pathname !== "/" ||
+      origin.search ||
+      origin.hash
+    )
+      throw new Error("The discussion test origin must be a loopback HTTP origin without credentials or a path.");
+    discussionTestOrigin = origin.origin;
+  }
   const liveBuildId = createLiveBuildId(liveTestBuild);
   const buildMode = argv.mode || "production";
 
@@ -127,6 +149,7 @@ module.exports = (env = {}, argv = {}) => {
       new webpack.DefinePlugin({
         __RYD_LIVE_BUILD_ID__: JSON.stringify(liveBuildId),
         __RYD_LIVE_TEST_BUILD__: JSON.stringify(liveTestBuild),
+        __RYD_DISCUSSION_TEST_ORIGIN__: JSON.stringify(discussionTestOrigin),
       }),
       ...(liveTestBuild
         ? [
@@ -151,7 +174,7 @@ module.exports = (env = {}, argv = {}) => {
           {
             from: "./Extensions/combined/manifest-chrome.json",
             to: "./chrome/manifest.json",
-            transform: manifestTransform,
+            transform: (content, filename) => manifestTransform(content, filename, discussionTestOrigin),
           },
           {
             from: "./Extensions/combined",
@@ -164,7 +187,7 @@ module.exports = (env = {}, argv = {}) => {
           {
             from: "./Extensions/combined/manifest-firefox.json",
             to: "./firefox/manifest.json",
-            transform: manifestTransform,
+            transform: (content, filename) => manifestTransform(content, filename, discussionTestOrigin),
           },
           {
             from: "./Extensions/combined",
@@ -177,7 +200,7 @@ module.exports = (env = {}, argv = {}) => {
           {
             from: "./Extensions/combined/manifest-safari.json",
             to: "./safari/manifest.json",
-            transform: manifestTransform,
+            transform: (content, filename) => manifestTransform(content, filename, discussionTestOrigin),
           },
         ],
       }),
diff --git a/webpack.discussion.spec.js b/webpack.discussion.spec.js
new file mode 100644
index 0000000..0ad2119
--- /dev/null
+++ b/webpack.discussion.spec.js
@@ -0,0 +1,32 @@
+const fs = require("node:fs");
+const createBuild = require("./webpack.config");
+
+function builtManifest(env) {
+  const build = createBuild(env, { mode: "production" });
+  const copy = build.plugins.find((plugin) => plugin.constructor.name === "CopyPlugin");
+  const transform = copy.patterns.find((pattern) => pattern.to === "./chrome/manifest.json").transform;
+  return JSON.parse(transform(fs.readFileSync("Extensions/combined/manifest-chrome.json"), "manifest-chrome.json"));
+}
+
+test("production packaging never adds a local discussion host", () => {
+  const manifest = builtManifest({});
+  expect(manifest.host_permissions).toEqual(["*://*.youtube.com/*", "*://returnyoutubedislikeapi.com/*"]);
+  expect(manifest.minimum_chrome_version).toBe("116");
+  expect(manifest.permissions).toContain("alarms");
+  expect(manifest.web_accessible_resources[0].resources).toContain("comments-bridge.js");
+});
+
+test("local discussion host is available only in an explicit isolated test build", () => {
+  expect(() => createBuild({ discussionTestOrigin: "http://127.0.0.1:5099" })).toThrow(/explicit live-test/);
+  for (const origin of [
+    "https://example.com",
+    "http://localhost/path",
+    "http://user@localhost",
+    "http://localhost?token=secret",
+  ]) {
+    expect(() => createBuild({ liveTest: true, discussionTestOrigin: origin })).toThrow(/loopback HTTP origin/);
+  }
+  expect(builtManifest({ liveTest: true, discussionTestOrigin: "http://127.0.0.1:5099" }).host_permissions).toContain(
+    "http://127.0.0.1/*",
+  );
+});