I wanted to set up a webmanifest/serviceworker to see how it worked. In Chrome you should see a little “download” icon on the right of the url bar. This will let you turn this page into a separate “app” window.
chrome://serviceworker-internals/ shows it is installed
Unfortunately looking at console logs, it seems like the serviceworker is sometimes being invoked when I visit other pages on my site, when I’m not visiting this page. I don’t know why. Frustrating. I can see it being fine at the top level but I can’ t recommend its use on a single page of my site.