Currently when an updated service worker is installed, the current page will reload automatically. This can be disorienting and it can even cause data to be lost, if the user starts entering data while the updated service worker is being installed.

In other words, we should discontinue skipWaiting by default. We could potentially show the service worker update button in the space where the admin bar would be displayed normally, if the admin bar is not already on the page. So we can reuse the admin bar area and class names and styles to show notices related to PWA, including offline status, new version of page available, refresh app, etc.

For more see #166 (comment).