Service Worker Issues In Edge Browser

Some unmentioned issues I’ve found trying to use Service Workers in Edge.

The ServiceWorkerRegistration.update method

From the Spec:
Returns: A Promise that resolves with a ServiceWorkerRegistration object.

Calling this is supposed to return a Promise with the SWRegistration object as a value. That value should contain a new Service Worker in the ‘installing’ property.

While this is correctly implemented in Chrome. In Edge there is no SWRegistration object returned. Which seems like a bug to me and means that I can’t use .update() as a cross browser safe implementation.

The ServiceWorkerRegistration.onupdatefound callback

From the spec:

The onupdatefound property of the ServiceWorkerRegistration interface is an EventListener property called whenever an event of type statechange is fired; it is fired any time the ServiceWorkerRegistration.installing property acquires a new service worker.

So if you listened to onupdatefound and then called SWRegistration.update(), then changed the sw.js file. The event should fire. It does in Chrome, but not in Edge.