docs: function(settings) {
        this.addSettings(settings);
  
        // register the service worker
        _serviceWorker.register(_settings['service-worker-url'], _settings['registration-options']).then(function(registration) {
          // Registration was successful
          if (_debugState) {
            console.log('Service worker registration successful with scope: %c'+registration.scope, _debugStyle);
          }
  
          // Send the settings to the service worker
          var messenger = registration.installing || _serviceWorker.controller || registration.active;
          messenger.postMessage({'action': 'set-settings', 'settings': _settings});
  
        }).catch(function(err) {
          // registration failed :(
          if (_debugState) {
            console.log('Service worker registration failed: %c'+err, _debugStyle);
          }
        });
      }