self.onmessage = function (event) {
  console.log(event.data);
  const action = event.data.action;
  switch(action) {
    case 'save':
      token = event.data.token;
      break;
    case 'load':
      console.log(token);
      break;
    default:
      console.error('Invalid action');
      return;
  }
  self.postMessage(true);
}