Merge feature/channel-card-enrich: channel About-tab enrichment + fixes

About tab now shows country/language/topics/keywords (migration 0055_channel_keywords);
Discovery tab links each channel to its in-app page; fixes: tab-switch header shift
(scrollbar-gutter:stable), hide the Source filter on the channel-scoped feed, recover a
throttled channel banner (retry + cache-buster), and match the no-banner fallback bar to
the banner height so the avatar no longer overlaps Back. /code-review findings fixed;
E2E + user UAT passed.

backend/alembic/versions/0055_channel_keywords.py

@@ -0,0 +1,23 @@
+"""channels.keywords: creator keyword tags from brandingSettings (About tab)
+
+Revision ID: 0055_channel_keywords
+Revises: 0054_audit_log
+Create Date: 2026-07-12
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+revision: str = "0055_channel_keywords"
+down_revision: Union[str, None] = "0054_audit_log"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column("channels", sa.Column("keywords", sa.Text(), nullable=True))
+
+
+def downgrade() -> None:
+    op.drop_column("channels", "keywords")

backend/app/models.py

@@ -180,6 +180,9 @@ class Channel(Base, TimestampMixin):
     topic_categories: Mapped[list | None] = mapped_column(JSON)
     default_language: Mapped[str | None] = mapped_column(String(16))
     country: Mapped[str | None] = mapped_column(String(8))
+    # Creator keyword tags (brandingSettings.channel.keywords) — a single space-separated string,
+    # multi-word tags quoted; the client parses it into chips for the About tab.
+    keywords: Mapped[str | None] = mapped_column(Text)
 
     # Sync bookkeeping.
     details_synced_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))

backend/app/routes/channels.py

@@ -233,6 +233,9 @@ def _channel_detail_dict(
         "published_at": channel.published_at.isoformat() if channel.published_at else None,
         "external_links": channel.external_links or [],
         "country": channel.country,
+        "default_language": channel.default_language,
+        "topic_categories": channel.topic_categories or [],
+        "keywords": channel.keywords,
         "subscribed": subscribed,
         "explored": explored,
         "blocked": blocked,

backend/app/sync/subscriptions.py

@@ -69,6 +69,7 @@ def apply_channel_details(db: Session, items: list[dict]) -> None:
         channel.banner_url = branding.get("image", {}).get("bannerExternalUrl")
         channel.external_links = _external_links(branding)
         channel.topic_categories = topics.get("topicCategories")
+        channel.keywords = (branding.get("channel") or {}).get("keywords")
         channel.details_synced_at = now
 
 

frontend/src/components/ChannelDiscovery.tsx

@@ -18,9 +18,11 @@ import { useConfirm } from "./ConfirmProvider";
 export default function ChannelDiscovery({
   canWrite,
   onOpenWizard,
+  onViewChannel,
 }: {
   canWrite: boolean;
   onOpenWizard: () => void;
+  onViewChannel: (id: string, name: string) => void;
 }) {
   const { t } = useTranslation();
   const qc = useQueryClient();
@@ -76,7 +78,13 @@ export default function ChannelDiscovery({
       filter: { kind: "text", get: (c) => `${c.title ?? ""} ${c.handle ?? ""}` },
       cardPrimary: true,
       render: (c) => (
-        <ChannelLink id={c.id} title={c.title} handle={c.handle} thumbnailUrl={c.thumbnail_url} />
+        <ChannelLink
+          id={c.id}
+          title={c.title}
+          handle={c.handle}
+          thumbnailUrl={c.thumbnail_url}
+          onView={() => onViewChannel(c.id, c.title ?? c.id)}
+        />
       ),
     },
     subsColumn<DiscoveredChannel>(t),

frontend/src/components/ChannelPage.tsx

@@ -10,6 +10,40 @@ import { notifyYouTubeActionError } from "../lib/youtubeErrors";
 import { api, type FeedFilters, type Me } from "../lib/api";
 import { channelYouTubeUrl, formatViews } from "../lib/format";
 
+// --- About-tab metadata helpers ---
+// ISO 3166-1 alpha-2 code → 🇺🇸 regional-indicator flag emoji.
+function countryFlag(code: string): string {
+  if (!/^[A-Za-z]{2}$/.test(code)) return "";
+  return String.fromCodePoint(...[...code.toUpperCase()].map((c) => 0x1f1e6 + c.charCodeAt(0) - 65));
+}
+function displayName(code: string, lang: string, type: "region" | "language"): string {
+  try {
+    return new Intl.DisplayNames([lang], { type }).of(type === "region" ? code.toUpperCase() : code) ?? code;
+  } catch {
+    return code;
+  }
+}
+// YouTube keywords are ONE space-separated string with multi-word tags quoted: gaming "let's play".
+function parseKeywords(s: string): string[] {
+  return (s.match(/"[^"]+"|\S+/g) ?? []).map((k) => k.replace(/^"|"$/g, "")).filter(Boolean);
+}
+// topicCategories are Wikipedia URLs (…/wiki/Music) → a readable label, de-duplicated.
+function topicLabels(urls: string[]): string[] {
+  const seen = new Set<string>();
+  for (const url of urls) {
+    const seg = url.split("/wiki/")[1] ?? url.split("/").pop() ?? url;
+    let label = seg;
+    try {
+      label = decodeURIComponent(seg);
+    } catch {
+      /* keep raw */
+    }
+    label = label.replace(/_/g, " ").trim();
+    if (label) seen.add(label);
+  }
+  return [...seen];
+}
+
 // A dedicated channel page: an "About"-style header (banner, avatar, stats, subscribe) over the
 // channel's videos (the catalog filtered to this channel). For an un-subscribed channel it
 // auto-ingests recent uploads in the background ("explore") so they're browsable immediately,
@@ -34,12 +68,20 @@ export default function ChannelPage({
   const qc = useQueryClient();
   const confirm = useConfirm();
   const [tab, setTab] = useState<"videos" | "about">("videos");
+  // The banner URL is valid, but googleusercontent intermittently throttles it when the channel
+  // page fires the banner + avatar + ~16 thumbnails in one burst — the request is dropped and the
+  // browser then NEGATIVE-CACHES the miss, so the banner stays broken even though a retry would
+  // succeed. So on error we retry a few times with a cache-buster (forcing a fresh request), and
+  // only fall back to the blank bar if it keeps failing (a genuinely dead URL — rare).
+  const MAX_BANNER_RETRIES = 3;
+  const [bannerAttempt, setBannerAttempt] = useState(0);
 
   const detail = useQuery({
     queryKey: ["channel", channelId],
     queryFn: () => api.channelDetail(channelId),
   });
   const ch = detail.data;
+  useEffect(() => setBannerAttempt(0), [ch?.banner_url]); // fresh channel/banner → try again
 
   // Background auto-ingest ("explore") of an un-subscribed channel's uploads.
   const [nextToken, setNextToken] = useState<string | null | undefined>(undefined);
@@ -147,16 +189,23 @@ export default function ChannelPage({
     ch?.total_view_count != null ? t("channel.totalViews", { formatted: formatViews(ch.total_view_count) }) : null,
     joined ? t("channel.joined", { date: joined }) : null,
   ].filter(Boolean) as string[];
+  const topics = ch?.topic_categories?.length ? topicLabels(ch.topic_categories) : [];
+  const keywords = ch?.keywords ? parseKeywords(ch.keywords) : [];
+  const hasAboutDetails =
+    !!ch?.country || !!ch?.default_language || topics.length > 0 || keywords.length > 0;
   const tabClass = (active: boolean) =>
     active
       ? "pb-2 text-sm font-medium border-b-2 border-fg text-fg"
       : "pb-2 text-sm text-muted hover:text-fg border-b-2 border-transparent";
 
   return (
-    <main className="flex-1 min-w-0 overflow-y-auto">
+    // scrollbar-gutter:stable reserves the scrollbar track on BOTH tabs, so switching between the
+    // tall Videos tab (scrollbar) and the short About tab (no scrollbar) no longer shifts the
+    // header/logo/buttons horizontally as the scrollbar appears/disappears.
+    <main className="flex-1 min-w-0 overflow-y-auto [scrollbar-gutter:stable]">
       {/* Banner + back — OPTION C: inset, rounded card (not full-bleed) */}
       <div className="relative px-4 sm:px-6 pt-3">
-        {ch?.banner_url ? (
+        {ch?.banner_url && bannerAttempt <= MAX_BANNER_RETRIES ? (
           // Match YouTube's banner: the stored bannerExternalUrl is the full 16:9 template at a
           // low default size, so request a crisp wide version (=w1707) and object-cover the
           // desktop "safe area" — the centre 2560×423 (~6:1) band.
@@ -165,13 +214,27 @@ export default function ChannelPage({
             style={{ aspectRatio: "2560 / 423", maxHeight: "150px" }}
           >
             <img
-              src={`${ch.banner_url}=w1707`}
+              // key forces a fresh <img> per attempt; the ?r= cache-buster on a retry bypasses the
+              // browser's negative cache (googleusercontent accepts an extra query param).
+              key={bannerAttempt}
+              src={`${ch.banner_url}=w1707${bannerAttempt ? `?r=${bannerAttempt}` : ""}`}
               alt=""
               className="w-full h-full object-cover object-center"
+              onError={() => {
+                if (bannerAttempt <= MAX_BANNER_RETRIES) {
+                  window.setTimeout(() => setBannerAttempt((a) => a + 1), 500 * (bannerAttempt + 1));
+                }
+              }}
             />
           </div>
         ) : (
-          <div className="h-14 w-full rounded-2xl bg-surface" />
+          // No banner (or a dead one): a neutral bar the SAME height as a real banner, so the
+          // overlapping avatar + the Back button have the same room and don't collide (a short bar
+          // let the -mt-8 avatar ride up into the Back button).
+          <div
+            className="w-full rounded-2xl bg-surface"
+            style={{ aspectRatio: "2560 / 423", maxHeight: "150px" }}
+          />
         )}
         <button
           onClick={onBack}
@@ -341,6 +404,48 @@ export default function ChannelPage({
               ))}
             </div>
           )}
+          {hasAboutDetails && (
+            <div className="mt-5 space-y-2.5 text-sm border-t border-border pt-4">
+              {ch?.country && (
+                <div className="flex gap-2">
+                  <span className="text-muted w-24 shrink-0">{t("channel.country")}</span>
+                  <span>
+                    {countryFlag(ch.country)} {displayName(ch.country, i18n.language, "region")}
+                  </span>
+                </div>
+              )}
+              {ch?.default_language && (
+                <div className="flex gap-2">
+                  <span className="text-muted w-24 shrink-0">{t("channel.language")}</span>
+                  <span>{displayName(ch.default_language, i18n.language, "language")}</span>
+                </div>
+              )}
+              {topics.length > 0 && (
+                <div className="flex gap-2">
+                  <span className="text-muted w-24 shrink-0 pt-0.5">{t("channel.topics")}</span>
+                  <div className="flex flex-wrap gap-1.5">
+                    {topics.map((tp) => (
+                      <span key={tp} className="glass-card px-2 py-0.5 rounded-full text-xs">
+                        {tp}
+                      </span>
+                    ))}
+                  </div>
+                </div>
+              )}
+              {keywords.length > 0 && (
+                <div className="flex gap-2">
+                  <span className="text-muted w-24 shrink-0 pt-0.5">{t("channel.keywords")}</span>
+                  <div className="flex flex-wrap gap-1.5">
+                    {keywords.map((kw, i) => (
+                      <span key={i} className="glass-card px-2 py-0.5 rounded-full text-xs">
+                        {kw}
+                      </span>
+                    ))}
+                  </div>
+                </div>
+              )}
+            </div>
+          )}
         </div>
       )}
     </main>

frontend/src/components/Channels.tsx

@@ -399,7 +399,7 @@ export default function Channels({
     return (
       <>
         {tabs}
-        <ChannelDiscovery canWrite={canWrite} onOpenWizard={onOpenWizard} />
+        <ChannelDiscovery canWrite={canWrite} onOpenWizard={onOpenWizard} onViewChannel={onViewChannel} />
       </>
     );
   }

frontend/src/components/Feed.tsx

@@ -552,6 +552,12 @@ export default function Feed({
             </button>
           );
         })}
+        {/* The Source filter (organic / include-search / search-only) is a global-catalog concept —
+            it selects how videos ENTERED the library. On a channel-scoped view we already show all
+            of this one channel's videos (librarySource is pinned to "all"), so the selector would
+            only offer a near-empty, confusing slice — hide it here. */}
+        {!channelScoped && (
+          <>
             <span className="mx-1 h-5 w-px bg-border" aria-hidden="true" />
             <label className="inline-flex items-center gap-1.5 text-xs text-muted">
               <span>{t("feed.source.label")}</span>
@@ -571,6 +577,8 @@ export default function Feed({
                 <option value="search">{t("feed.source.only")}</option>
               </select>
             </label>
+          </>
+        )}
         <span className="mx-1 h-5 w-px bg-border" aria-hidden="true" />
         <span className="text-xs text-muted whitespace-nowrap">
           {countQuery.data

frontend/src/i18n/locales/de/channel.json

@@ -19,5 +19,9 @@
   "noDescription": "Dieser Kanal hat keine Beschreibung.",
   "block": "Kanal blockieren",
   "unblock": "Blockierung aufheben",
-  "blockedBadge": "Blockiert"
+  "blockedBadge": "Blockiert",
+  "country": "Land",
+  "language": "Sprache",
+  "topics": "Themen",
+  "keywords": "Schlagwörter"
 }

frontend/src/i18n/locales/en/channel.json

@@ -19,5 +19,9 @@
   "noDescription": "This channel has no description.",
   "block": "Block channel",
   "unblock": "Unblock channel",
-  "blockedBadge": "Blocked"
+  "blockedBadge": "Blocked",
+  "country": "Country",
+  "language": "Language",
+  "topics": "Topics",
+  "keywords": "Keywords"
 }

frontend/src/i18n/locales/hu/channel.json

@@ -19,5 +19,9 @@
   "noDescription": "Ennek a csatornának nincs leírása.",
   "block": "Csatorna tiltása",
   "unblock": "Tiltás feloldása",
-  "blockedBadge": "Tiltva"
+  "blockedBadge": "Tiltva",
+  "country": "Ország",
+  "language": "Nyelv",
+  "topics": "Témák",
+  "keywords": "Kulcsszavak"
 }

frontend/src/lib/api.ts

@@ -96,6 +96,9 @@ export interface ChannelDetail {
   published_at: string | null;
   external_links: ChannelLink[];
   country: string | null;
+  default_language: string | null;
+  topic_categories: string[];
+  keywords: string | null;
   subscribed: boolean;
   explored: boolean;
   blocked: boolean;