I agree it sucks, but iOS's service worker policy gave me no other option. Every other browser is just fine having the timeout running in the background, and I in fact have both codepaths running simultaneously so any other browser can work offline.

Funny that I provide a fully working code sample of how to do what the parent wants, explain the caveats associated with it, and get downvoted because Apple crippled their service workers... ok then, Hackers.