Just one detail about this test. Now we are testing we dispatch as much tests as settings but not **one event by setting**. To test this modify the event listener this way:

```javascript
var alreadyDispatched = {};
window.addEventListener('customization', function customizer(event) {
  var setting = event.detail.setting;
  if (alreadyDispatched[setting]) {
    assert.ok(false, 'The settting ' + setting + `' was dispatched twice.');
    done();
    return;
  }

  alreadyDispatched[setting] = true;
  if (eventsToDispatch == ++eventsDispatched) {
    window.removeEventListener('customization', customizer);
    done();
  }
});
```