diff --git a/src/components/ChatPanel.tsx b/src/components/ChatPanel.tsx
index c1ebbb1..3d2d35e 100644
--- a/src/components/ChatPanel.tsx
+++ b/src/components/ChatPanel.tsx
@@ -31,7 +31,11 @@ export default function ChatPanel({ chatId, fullscreen = false }: Props) {
   useEffect(() => {
     const unsub = wsClient.on("message.new", (data: any) => {
       if (data.chat_id === chatId) {
-        setMessages((prev) => [...prev, data as Message]);
+        setMessages((prev) => {
+          // Dedup by message id
+          if (prev.some((m) => m.id === data.id)) return prev;
+          return [...prev, data as Message];
+        });
       }
     });
     return () => { unsub?.(); };
diff --git a/src/main.tsx b/src/main.tsx
index 3d4bdea..c1ba65c 100644
--- a/src/main.tsx
+++ b/src/main.tsx
@@ -1,10 +1,9 @@
-import { StrictMode } from 'react'
+// StrictMode removed — causes double WS subscriptions (double useEffect)
+// import { StrictMode } from 'react'
 import { createRoot } from 'react-dom/client'
 import './index.css'
 import App from './App.tsx'
 
 createRoot(document.getElementById('root')!).render(
-  <StrictMode>
-    <App />
-  </StrictMode>,
+  <App />,
 )
\ No newline at end of file