text: const requests = [];
  let port = undefined;
  
  self.onmessage = e => {
    const message = e.data;
    if ('port' in message) {
      port = message.port;
      port.postMessage({ready: true});
    }
  };
  
  self.addEventListener('fetch', e => {
    const url = e.request.url;
    if (!url.includes('dummy?test')) {
      return;
    }
    port.postMessage({
      url: url,
      mode: e.request.mode,
      redirect: e.request.redirect,
      credentials: e.request.credentials,
      integrity: e.request.integrity,
      destination: e.request.destination
    });
    e.respondWith(Promise.reject());
  });
  