def _start_auto_refresh_thread(self):
        """
        Start the background thread that auto refreshes all clients according to
        `self.status_interval`.
        """
        def run():
            while True:
                time.sleep(self.status_interval)
                self.invalidate()

        t = threading.Thread(target=run)
        t.daemon = True
        t.start()
Start the background thread that auto refreshes all clients according to
        `self.status_interval`.