update

frontend/src/contexts/ChatContext.tsx

@@ -56,7 +56,6 @@ export const ChatProvider: React.FC<ChatProviderProps> = ({ children }) => {
   const connected = data?.connected ?? false;
   const loginName = data?.loginName ?? null;
 
-  const prevUnreadRef = useRef<Map<string, number>>(new Map());
   const isInitializedRef = useRef(false);
 
   // Reset initialization flag when disconnected