Make sure state is not updated after dismount

state_update.tsx

useEffect(() => {
    let isMounted = true; // Used to make sure we don't make state update after component dismount.
    const socket = io('ws://localhost:5000/live');
    socket.on('connect', function () {
      console.log('CONNECTED');
    });
    socket.on('disconnect', function () {
      console.log('DISCONNECTED');
    });
    socket.on('update', function (payload: any) {
      fetch(`http://localhost:5000/images/${payload.src}`).then(() => {
        if (isMounted) {
          setLive(payload.src);
          socket.emit('ready');
        }
      });
    });
    
      /** On component destroy. */
    return () => {
      socket.close();
      isMounted = false;
    };