Make duplicate notification IDs non-fatal

The notification.Error there is unhandled otherwise.

doc/changelog.asciidoc

@@ -25,6 +25,8 @@ Fixed
 - Crash when trying to use the `DocumentPictureInPicture` JS API, such as done
   by the new Google Workspaces Huddle feature. The API is unsupported by
   QtWebEngine and now correctly disabled on the JS side. (#8449)
+- Crash when a buggy notification presenter returns a duplicate ID (now an
+  error is shown instead).
 
 [[v3.4.0]]
 v3.4.0 (2024-12-14)

qutebrowser/browser/webengine/notification.py

@@ -286,7 +286,10 @@ class NotificationBridgePresenter(QObject):
 
         if replaces_id is None:
             if notification_id in self._active_notifications:
-                raise Error(f"Got duplicate id {notification_id}")
+                message.error(f"Got duplicate notification id {notification_id} "
+                              f"from {self._adapter.NAME}")
+                self._drop_adapter()
+                return
 
         qt_notification.show()
         self._active_notifications[notification_id] = qt_notification