def _maybe_quit_if_no_windows_open(self) -> None:
        """Check if there are any open windows and decide whether we should quit."""
        # keep daemon running after close
        if self.config.get('daemon'):
            return
        # check if a wizard is in progress
        with self._num_wizards_lock:
            if self._num_wizards_in_progress > 0 or len(self.windows) > 0:
                return
        self.app.quit()
Check if there are any open windows and decide whether we should quit.
electrum/gui/qt/__init__.py