diff --git a/src/frontend/src/App.tsx b/src/frontend/src/App.tsx
index b066552..55c8778 100644
--- a/src/frontend/src/App.tsx
+++ b/src/frontend/src/App.tsx
@@ -38,6 +38,7 @@ export default function App() {
 
   useEffect(() => {
     startPolling();
+    startSSE();
     // P1: 活跃度追踪
     const onActivity = () => { (window as any).__markActivity?.(); };
     window.addEventListener('mousemove', onActivity);
@@ -45,6 +46,7 @@ export default function App() {
     window.addEventListener('click', onActivity);
     return () => {
       stopPolling();
+      stopSSE();
       window.removeEventListener('mousemove', onActivity);
       window.removeEventListener('keydown', onActivity);
       window.removeEventListener('click', onActivity);