fix: multi-tab concurrency and metadata sync improvements

.gitignore

@@ -14,6 +14,8 @@ node_modules/
 dist/
 build/
 .vite/
+frontend/auto-imports.d.ts
+frontend/components.d.ts
 
 backend/static/
 backend/data/

backend/app/services/browser_session_service.py

@@ -141,6 +141,8 @@ class BrowserSessionService:
             self._sessions[session.id] = session
             self._profiles[profile_key] = session.id
             self._touch(session.id)
+            # Register listeners for the initial tab
+            self._setup_tab_listeners(session, page)
             # Register page capture for multi-tab support
             context.on("page", lambda p: self._handle_new_page(session, p))
             # Evict again after adding the new session so cap is enforced immediately
@@ -160,14 +162,31 @@ class BrowserSessionService:
 
     def _handle_new_page(self, session: BrowserSession, page: Any) -> None:
         """Capture a new page opened by the remote browser (e.g. target="_blank")."""
+        asyncio.create_task(self._register_new_page(session, page))
+
+    def _setup_tab_listeners(self, session: BrowserSession, page: Any) -> None:
+        """Register navigation and state listeners to bump tab_revision."""
+        def bump_revision(_=None):
+            session.tab_revision += 1
+
+        page.on("domcontentloaded", bump_revision)
+        page.on("load", bump_revision)
+        page.on("framenavigated", bump_revision)
+        page.on("close", bump_revision)
+
+    async def _register_new_page(self, session: BrowserSession, page: Any) -> None:
         tab_id = uuid4().hex
         tab = BrowserTab(id=tab_id, page=page, created_at=asyncio.get_event_loop().time())
+        
+        async with session.lock:
             session.tabs[tab_id] = tab
             session.active_tab_id = tab_id
             session.tab_revision += 1
             logger.info("session %s: captured new tab %s (total: %d)", session.id[:12], tab_id[:8], len(session.tabs))
+
+        self._setup_tab_listeners(session, page)
         # Best-effort: bring to front and reset zoom
-        asyncio.create_task(self._init_new_tab(session, tab))
+        await self._init_new_tab(session, tab)
 
     async def _init_new_tab(self, session: BrowserSession, tab: BrowserTab) -> None:
         try:
@@ -399,7 +418,8 @@ class BrowserSessionService:
         tabs = []
         # We might need to prune closed pages during state generation too
         closed_ids = []
-        for tid, tab in session.tabs.items():
+        # Use list() to avoid RuntimeError if tabs dict changes during iteration
+        for tid, tab in list(session.tabs.items()):
             if tab.page.is_closed():
                 closed_ids.append(tid)
                 continue
@@ -734,6 +754,8 @@ class BrowserSessionService:
             )
             self._sessions[session.id] = session
             self._touch(session.id)
+            # Register listeners for the initial tab
+            self._setup_tab_listeners(session, page)
             # Register page capture
             context.on("page", lambda p: self._handle_new_page(session, p))
         # Start CDP network capture BEFORE the initial page load,

backend/test_browser_tabs.py

@@ -12,6 +12,8 @@ def service():
 def session(service):
     fake_context = AsyncMock()
     fake_page = AsyncMock()
+    # Playwright's page.on is synchronous
+    fake_page.on = MagicMock()
     fake_page.is_closed = MagicMock(return_value=False)
     fake_page.url = "https://initial.test"
     fake_page.title = AsyncMock(return_value="Initial Tab")
@@ -34,6 +36,7 @@ def session(service):
 @pytest.mark.asyncio
 async def test_tab_capture(service, session):
     new_page = AsyncMock()
+    new_page.on = MagicMock()
     new_page.is_closed = MagicMock(return_value=False)
     new_page.url = "https://new.test"
     new_page.title = AsyncMock(return_value="New Tab")
@@ -42,6 +45,9 @@ async def test_tab_capture(service, session):
     # Simulate page capture
     service._handle_new_page(session, new_page)
     
+    # Wait for the background registration task to finish
+    await asyncio.sleep(0.1)
+    
     assert len(session.tabs) == 2
     assert session.active_tab_id != "tab1"
     new_tab_id = session.active_tab_id