fix(ui): robust avatars — no-referrer + graceful fallback

Channel/account avatars come from Google's image CDNs (yt3.ggpht.com,
lh3.googleusercontent.com). On a feed page dozens load at once; the CDN
rate-limits the referrer-bearing burst (429), so a random subset rendered the
browser's broken-image icon (the URLs themselves are valid — verified 200).

Add a shared <Avatar> that sets referrerPolicy="no-referrer" (which the CDNs
serve without throttling) and falls back to a neutral initial placeholder on
error instead of the broken-image icon. Use it for video-card, player, channel
manager, header and settings avatars.

frontend/src/components/Avatar.tsx

@@ -0,0 +1,48 @@
+import { useEffect, useState } from "react";
+
+// Avatar image with a graceful fallback.
+//
+// Uses referrerPolicy="no-referrer" because Google's avatar CDNs
+// (yt3.ggpht.com / lh3.googleusercontent.com) rate-limit bursts of
+// referrer-bearing requests — when a feed page fires dozens of avatar loads at
+// once, a random subset gets throttled (HTTP 429) and the browser shows its
+// broken-image icon. Dropping the referrer makes those CDNs serve the images.
+// If a load still fails we render a neutral placeholder (optionally an initial)
+// instead of the broken-image icon.
+export default function Avatar({
+  src,
+  alt = "",
+  fallback,
+  className = "",
+}: {
+  src?: string | null;
+  alt?: string;
+  fallback?: string; // a name/title; its first letter is shown when there's no image
+  className?: string;
+}) {
+  const [failed, setFailed] = useState(false);
+  useEffect(() => setFailed(false), [src]);
+
+  if (src && !failed) {
+    return (
+      <img
+        src={src}
+        alt={alt}
+        loading="lazy"
+        referrerPolicy="no-referrer"
+        onError={() => setFailed(true)}
+        className={className}
+      />
+    );
+  }
+
+  const initial = fallback?.trim()?.[0]?.toUpperCase() ?? "";
+  return (
+    <div
+      className={`bg-card grid place-items-center font-semibold text-muted select-none ${className}`}
+      aria-hidden
+    >
+      {initial}
+    </div>
+  );
+}

frontend/src/components/Channels.tsx

@@ -16,6 +16,7 @@ import { api, type ManagedChannel, type Tag } from "../lib/api";
 import { formatEta } from "../lib/format";
 import { notify } from "../lib/notifications";
 import Tooltip from "./Tooltip";
+import Avatar from "./Avatar";
 
 export default function Channels({
   canWrite,
@@ -332,11 +333,11 @@ function ChannelRow({
         </div>
       </Tooltip>
 
-      {c.thumbnail_url ? (
+      <Avatar
-        <img src={c.thumbnail_url} alt="" className="w-10 h-10 rounded-full shrink-0" />
+        src={c.thumbnail_url}
-      ) : (
+        fallback={c.title ?? ""}
-        <div className="w-10 h-10 rounded-full bg-card shrink-0" />
+        className="w-10 h-10 rounded-full shrink-0"
-      )}
+      />
 
       <div className="min-w-0 flex-1">
         <button onClick={onView} className="text-sm font-semibold truncate hover:text-accent block max-w-full text-left">

frontend/src/components/Header.tsx

@@ -4,6 +4,7 @@ import type { FeedFilters, Me } from "../lib/api";
 import type { Page } from "../lib/urlState";
 import SyncStatus from "./SyncStatus";
 import NotificationCenter from "./NotificationCenter";
+import AvatarImg from "./Avatar";
 
 export default function Header({
   me,
@@ -70,12 +71,12 @@ export default function Header({
 }
 
 function Avatar({ me, className = "" }: { me: Me; className?: string }) {
-  return me.avatar_url ? (
+  return (
-    <img src={me.avatar_url} alt="" className={`rounded-full ${className}`} />
+    <AvatarImg
-  ) : (
+      src={me.avatar_url}
-    <div className={`rounded-full bg-card grid place-items-center font-semibold ${className}`}>
+      fallback={me.display_name ?? me.email}
-      {(me.display_name?.[0] ?? me.email[0] ?? "?").toUpperCase()}
+      className={`rounded-full ${className}`}
-    </div>
+    />
   );
 }
 

frontend/src/components/PlayerModal.tsx

@@ -2,6 +2,7 @@ import { useEffect, useRef, useState, type ReactNode } from "react";
 import { createPortal } from "react-dom";
 import { useQuery } from "@tanstack/react-query";
 import { ArrowLeft, Check, CheckCheck, X } from "lucide-react";
+import Avatar from "./Avatar";
 import { api, type Video } from "../lib/api";
 import { formatDuration, formatViews, relativeTime } from "../lib/format";
 
@@ -454,10 +455,10 @@ export default function PlayerModal({
               When navigated to a linked video we only have its author (from the player),
               so we show that as plain text and hide feed-video-specific bits. */}
           <div className="flex items-center gap-3 mt-3">
-            {!navigated && video.channel_thumbnail && (
+            {!navigated && (
-              <img
+              <Avatar
                 src={video.channel_thumbnail}
-                alt=""
+                fallback={video.channel_title ?? ""}
                 className="w-9 h-9 rounded-full shrink-0"
               />
             )}

frontend/src/components/SettingsPanel.tsx

@@ -4,6 +4,7 @@ import { Bell, Check, History, Monitor, Pause, Play, RefreshCw, User, UserPlus,
 import { SCHEMES, type Scheme, type ThemePrefs } from "../lib/theme";
 import { api, type Invite, type Me } from "../lib/api";
 import { formatEta, quotaActionLabel } from "../lib/format";
+import Avatar from "./Avatar";
 import {
   configureNotifications,
   getNotifSettings,
@@ -468,13 +469,11 @@ function Account({ me }: { me: Me }) {
     <>
     <Section title="Account">
       <div className="flex items-center gap-3 mb-3">
-        {me.avatar_url ? (
+        <Avatar
-          <img src={me.avatar_url} alt="" className="w-12 h-12 rounded-full" />
+          src={me.avatar_url}
-        ) : (
+          fallback={me.display_name ?? me.email}
-          <div className="w-12 h-12 rounded-full bg-card grid place-items-center font-semibold">
+          className="w-12 h-12 rounded-full"
-            {(me.display_name?.[0] ?? me.email[0] ?? "?").toUpperCase()}
+        />
-          </div>
-        )}
         <div className="min-w-0">
           <div className="font-semibold truncate">{me.display_name ?? me.email.split("@")[0]}</div>
           <div className="text-xs text-muted truncate">{me.email}</div>

frontend/src/components/VideoCard.tsx

@@ -1,4 +1,5 @@
 import { Bookmark, Check, CheckCheck, Eye, EyeOff, ListFilter } from "lucide-react";
+import Avatar from "./Avatar";
 import clsx from "clsx";
 import type { Video } from "../lib/api";
 import { formatDuration, formatViews, relativeTime } from "../lib/format";
@@ -203,14 +204,11 @@ export default function VideoCard({
     >
       <Thumb video={video} className="aspect-video" onOpen={onOpen} />
       <div className="flex gap-3 mt-2.5 px-0.5 pb-0.5">
-        {video.channel_thumbnail && (
+        <Avatar
-          <img
+          src={video.channel_thumbnail}
-            src={video.channel_thumbnail}
+          fallback={video.channel_title ?? ""}
-            alt=""
+          className="w-9 h-9 rounded-full shrink-0 mt-0.5"
-            loading="lazy"
+        />
-            className="w-9 h-9 rounded-full shrink-0 mt-0.5"
-          />
-        )}
         <div className="min-w-0 flex-1">
           {title}
           <a