I am trying to understand Periodic Background Sync, and the official demo appears to be broken. This is the link to the official demo app that Google provides: https://webplatformapis.com/periodic_sync/periodicSync_improved.html
It's even on their documentation here: https://web.dev/periodic-background-sync/
I installed the PWA they provided on my PC and my Android phone, and I'm still not experiencing any form of background synchronization, unless I click on "Sync Manually" on the app. There's no Network activity in DevTools either when I investigate.
Does anyone know if the Periodic Background Sync API works at all? Even MDN appears to have draft content about it.