diff --git a/frontend/app/components/assistant-ui/thread.tsx b/frontend/app/components/assistant-ui/thread.tsx
index 76fa85b..33123da 100644
--- a/frontend/app/components/assistant-ui/thread.tsx
+++ b/frontend/app/components/assistant-ui/thread.tsx
@@ -424,6 +424,9 @@ const ChatTopActions: FC = () => {
 	const [workspaceOpen, setWorkspaceOpen] = useState(false);
 	const normalizedSessionId = useCurrentThreadSessionId({
 		includePending: true,
+		// 工作区切换必须绑定当前可见会话；空白新会话不能回退到上一个
+		// activeSessionId，否则会把 Jupyter 工作区切到旧会话上。
+		includeActive: false,
 	});
 	const workspaceStatus = useJupyterWorkspaceStatus(normalizedSessionId);
 
@@ -849,6 +852,7 @@ const Composer: FC = () => {
 	const replayedRun = useReplayedRunState();
 	const workspaceSessionId = useCurrentThreadSessionId({
 		includePending: true,
+		includeActive: false,
 	});
 	return (
 		<ComposerPrimitive.Root className="aui-composer-root relative flex w-full flex-col">