tenfourfox/devtools/shared/webconsole/test/helper_serviceworker.js

console.log('script evaluation');

addEventListener('install', function(evt) {
  console.log('install event');
});

addEventListener('activate', function(evt) {
  console.log('activate event');
});

addEventListener('fetch', function(evt) {
  console.log('fetch event: ' + evt.request.url);
  evt.respondWith(new Response('Hello world'));
});

addEventListener('message', function(evt) {
  console.log('message event: ' + evt.data.message);
  evt.source.postMessage({ type: 'PONG' });
});