fix(ui): restore context panel session chats

packages/ui/src/App.tsx

@@ -54,7 +54,11 @@ import { MCP_OAUTH_CALLBACK_PATH } from '@/components/sections/mcp/mcpOAuth';
 import { lazyWithChunkRecovery } from '@/lib/chunkLoadRecovery';
 import { useI18n } from '@/lib/i18n';
 import { applyMobileKeyboardMode } from '@/lib/mobileKeyboardMode';
-import { isEmbeddedSessionChat } from '@/components/layout/contextPanelEmbeddedChat';
+import {
+  EMBEDDED_VISIBILITY_UPDATE,
+  isEmbeddedSessionChat,
+  requestEmbeddedSessionVisibility,
+} from '@/components/layout/contextPanelEmbeddedChat';
 import { SyncAppEffects } from '@/apps/AppEffects';
 import { resetAppForRuntimeEndpointChange } from '@/apps/runtimeEndpointReset';
 import { useAppFontEffects } from '@/apps/useAppFontEffects';
@@ -538,17 +542,16 @@ function App({ apis }: AppProps) {
     }
 
     const applyVisibility = (payload?: EmbeddedVisibilityPayload) => {
-      const nextVisible = payload?.visible === true;
+      setIsEmbeddedVisible(payload?.visible === true);
-      setIsEmbeddedVisible(nextVisible);
     };
 
     const handleMessage = (event: MessageEvent) => {
-      if (event.origin !== window.location.origin) {
+      if (event.origin !== window.location.origin || event.source !== window.parent) {
         return;
       }
 
       const data = event.data as { type?: unknown; payload?: EmbeddedVisibilityPayload };
-      if (data?.type !== 'openchamber:embedded-visibility') {
+      if (data?.type !== EMBEDDED_VISIBILITY_UPDATE) {
         return;
       }
 
@@ -561,6 +564,7 @@ function App({ apis }: AppProps) {
 
     scopedWindow.__openchamberSetEmbeddedVisibility = applyVisibility;
     window.addEventListener('message', handleMessage);
+    requestEmbeddedSessionVisibility();
 
     return () => {
       window.removeEventListener('message', handleMessage);

packages/ui/src/components/layout/ContextPanel.tsx

@@ -38,6 +38,8 @@ import { Icon } from "@/components/icon/Icon";
 import {
   EMBEDDED_RUNTIME_BOOTSTRAP_REQUEST,
   EMBEDDED_RUNTIME_BOOTSTRAP_RESPONSE,
+  EMBEDDED_VISIBILITY_REQUEST,
+  EMBEDDED_VISIBILITY_UPDATE,
   getActiveEmbeddedSessionChatTab,
   getOrCreateEmbeddedSessionChatURL,
   type EmbeddedSessionChatURLCacheEntry,
@@ -803,27 +805,34 @@ export const ContextPanel: React.FC = () => {
     }
   }, [allowPromptingSubagentSessions]);
 
+  const postEmbeddedVisibilityToChat = React.useCallback((
+    tabID: string,
+    frame: HTMLIFrameElement,
+    targetOrigin: string,
+  ) => {
+    const frameWindow = frame.contentWindow;
+    if (!frameWindow) {
+      return;
+    }
+
+    frameWindow.postMessage(
+      {
+        type: EMBEDDED_VISIBILITY_UPDATE,
+        payload: { visible: activeChatTabID === tabID },
+      },
+      targetOrigin,
+    );
+  }, [activeChatTabID]);
+
   const postEmbeddedVisibilityToChats = React.useCallback(() => {
     if (typeof window === 'undefined') {
       return;
     }
 
     for (const [tabID, frame] of chatFrameRefs.current.entries()) {
-      const frameWindow = frame.contentWindow;
+      postEmbeddedVisibilityToChat(tabID, frame, window.location.origin);
-      if (!frameWindow) {
-        continue;
-      }
-
-      const payload = { visible: activeChatTabID === tabID };
-      frameWindow.postMessage(
-        {
-          type: 'openchamber:embedded-visibility',
-          payload,
-        },
-        window.location.origin,
-      );
     }
-  }, [activeChatTabID]);
+  }, [postEmbeddedVisibilityToChat]);
 
   React.useEffect(() => {
     if (typeof window === 'undefined') {
@@ -835,13 +844,18 @@ export const ContextPanel: React.FC = () => {
         return;
       }
 
-      const isKnownChatFrame = Array.from(chatFrameRefs.current.values())
+      const sourceChatFrame = Array.from(chatFrameRefs.current.entries())
-        .some((frame) => frame.contentWindow === event.source);
+        .find(([, frame]) => frame.contentWindow === event.source);
-      if (!isKnownChatFrame) {
+      if (!sourceChatFrame) {
         return;
       }
 
       const data = event.data as { type?: unknown; requestId?: unknown };
+      if (data?.type === EMBEDDED_VISIBILITY_REQUEST) {
+        const [tabID, frame] = sourceChatFrame;
+        postEmbeddedVisibilityToChat(tabID, frame, event.origin);
+        return;
+      }
       if (data?.type === EMBEDDED_RUNTIME_BOOTSTRAP_REQUEST) {
         if (typeof data.requestId !== 'string' || !data.requestId) return;
         const runtimeKey = getRuntimeKey();
@@ -882,7 +896,7 @@ export const ContextPanel: React.FC = () => {
 
     window.addEventListener('message', handleMessage);
     return () => window.removeEventListener('message', handleMessage);
-  }, [postChatSettingsSyncToEmbeddedChat, postThemeSyncToEmbeddedChat, setThemeMode, themeMode]);
+  }, [postChatSettingsSyncToEmbeddedChat, postEmbeddedVisibilityToChat, postThemeSyncToEmbeddedChat, setThemeMode, themeMode]);
 
   React.useLayoutEffect(() => {
     const hasAnyChatTab = tabs.some((tab) => tab.mode === 'chat');

packages/ui/src/components/layout/__tests__/issue-2815-sessionChatIframesMountAllTabs.test.ts

@@ -19,6 +19,7 @@ import {
 } from '../contextPanelEmbeddedChat';
 
 const __dirname = dirname(fileURLToPath(import.meta.url));
+const appSource = readFileSync(join(__dirname, '..', '..', '..', 'App.tsx'), 'utf-8');
 const contextPanelSource = readFileSync(join(__dirname, '..', 'ContextPanel.tsx'), 'utf-8');
 
 type FixtureTab = {
@@ -117,6 +118,7 @@ describe('issue #2815 active-only chat iframe source guard', () => {
     expect(block).toContain('<iframe');
     expect(block).toContain('key={activeChatTab.id}');
     expect(block).toContain('src={activeChatSrc}');
+    expect(block).toContain('postEmbeddedVisibilityToChats();');
     expect(block).not.toContain("'block' : 'hidden'");
   });
 
@@ -128,6 +130,32 @@ describe('issue #2815 active-only chat iframe source guard', () => {
       "const activeChatSessionID = isOpen && activeTab?.mode === 'chat'",
     );
   });
+
+  test('answers the mounted iframe visibility handshake from the active tab', () => {
+    expect(contextPanelSource).toContain('data?.type === EMBEDDED_VISIBILITY_REQUEST');
+    expect(contextPanelSource).toContain('frame.contentWindow === event.source');
+    expect(contextPanelSource).toContain('payload: { visible: activeChatTabID === tabID }');
+  });
+
+  test('requests authoritative visibility after installing the iframe listener', () => {
+    const effectStart = appSource.indexOf('const applyVisibility = (payload?: EmbeddedVisibilityPayload) => {');
+    const listenerIndex = appSource.indexOf("window.addEventListener('message', handleMessage);", effectStart);
+    const requestIndex = appSource.indexOf('requestEmbeddedSessionVisibility();', effectStart);
+
+    expect(effectStart).toBeGreaterThan(-1);
+    expect(listenerIndex).toBeGreaterThan(effectStart);
+    expect(requestIndex).toBeGreaterThan(listenerIndex);
+  });
+
+  test('gates embedded chat subscriptions and background work on visibility', () => {
+    expect(appSource).toContain(
+      'const embeddedBackgroundWorkEnabled = !embeddedSessionChat || isEmbeddedVisible;',
+    );
+    expect(appSource).toContain('active={embeddedBackgroundWorkEnabled}');
+    expect(appSource).toContain(
+      'useWebNotificationStream({ enabled: embeddedBackgroundWorkEnabled });',
+    );
+  });
 });
 
 describe('issue #2815 persisted scenario', () => {

packages/ui/src/components/layout/contextPanelEmbeddedChat.test.ts

@@ -5,11 +5,13 @@ import {
   buildEmbeddedSessionChatURL,
   EMBEDDED_RUNTIME_BOOTSTRAP_REQUEST,
   EMBEDDED_RUNTIME_BOOTSTRAP_RESPONSE,
+  EMBEDDED_VISIBILITY_REQUEST,
   getOrCreateEmbeddedSessionChatURL,
   getActiveEmbeddedSessionChatTab,
   getEmbeddedSessionChatOriginSessionId,
   isEmbeddedSessionChat,
   requestEmbeddedSessionRuntimeBootstrap,
+  requestEmbeddedSessionVisibility,
   resetEmbeddedSessionChatCache,
   type EmbeddedSessionChatURLCacheEntry,
 } from './contextPanelEmbeddedChat';
@@ -171,6 +173,22 @@ describe('active embedded session chat', () => {
     expect(getActiveEmbeddedSessionChatTab(tabs, null)).toBeNull();
     expect(getActiveEmbeddedSessionChatTab(tabs, 'missing-chat')).toBeNull();
   });
+
+  test('requests authoritative visibility from the same-origin parent', () => {
+    installWindowLocation('http://127.0.0.1:5173/app?ocPanel=session-chat&sessionId=ses_1');
+    resetEmbeddedSessionChatCache();
+    const calls: Array<{ message: unknown; origin: string }> = [];
+    (window as unknown as { parent: { postMessage: (message: unknown, origin: string) => void } }).parent = {
+      postMessage: (message, origin) => calls.push({ message, origin }),
+    };
+
+    requestEmbeddedSessionVisibility();
+
+    expect(calls).toEqual([{
+      message: { type: EMBEDDED_VISIBILITY_REQUEST },
+      origin: 'http://127.0.0.1:5173',
+    }]);
+  });
 });
 
 describe('isEmbeddedSessionChat', () => {

packages/ui/src/components/layout/contextPanelEmbeddedChat.ts

@@ -28,6 +28,8 @@ export type EmbeddedSessionRuntimeBootstrap = {
 
 export const EMBEDDED_RUNTIME_BOOTSTRAP_REQUEST = 'openchamber:embedded-runtime-bootstrap-request';
 export const EMBEDDED_RUNTIME_BOOTSTRAP_RESPONSE = 'openchamber:embedded-runtime-bootstrap-response';
+export const EMBEDDED_VISIBILITY_REQUEST = 'openchamber:embedded-visibility-request';
+export const EMBEDDED_VISIBILITY_UPDATE = 'openchamber:embedded-visibility';
 const EMBEDDED_RUNTIME_BOOTSTRAP_TIMEOUT_MS = 5_000;
 const EMBEDDED_RUNTIME_BOOTSTRAP_RETRY_MS = 100;
 
@@ -104,6 +106,13 @@ export const requestEmbeddedSessionRuntimeBootstrap = (): Promise<EmbeddedSessio
   });
 };
 
+export const requestEmbeddedSessionVisibility = (): void => {
+  if (!isEmbeddedSessionChat() || typeof window === 'undefined' || !window.parent || window.parent === window) {
+    return;
+  }
+  window.parent.postMessage({ type: EMBEDDED_VISIBILITY_REQUEST }, window.location.origin);
+};
+
 const buildEmbeddedSessionChatURLSignature = (
   sessionID: string,
   directory: string | null,

packages/ui/src/stores/DOCUMENTATION.md

@@ -40,6 +40,13 @@ Examples:
 
 These stores coordinate visible app state, navigation, selected tabs, dialogs, and lightweight feature flags.
 
+Context-panel session chats mount only the active chat iframe. After installing
+its message listener, the iframe requests its authoritative visibility from the
+parent. The parent accepts requests only from a currently mounted chat frame and
+answers from the current active tab. Do not rely only on a parent `onLoad`
+notification: it can arrive before the iframe listener exists and leave a
+visible chat with background work and message subscriptions disabled.
+
 ### Session / project coordination stores
 
 Examples: