Request permission to use offline persistence (web) with Firebase Firestore?

Question

I am working on a major update to my app and I wanted to take advantage of Firestore's offline persistence (web) as a caching layer (as described in this recent Firebase video: https://youtu.be/iQOTjUko9WM ).

I have a tester who swears she has no security-related extensions installed. Or even any sort of third-party app meant to 'harden' a device.

But my app's offline persistence does not work for her... and only her, out of about 20 testers.

In Chrome she sees a message "Audit usage of navigator.useragent navigator.appversion and navigator.platform" in her console (but hasn't toggled the triangle to see if there is more info).

In Edge she sees "tracking prevention blocked access to storage for..." and that is followed by "FirebaseError: Failed to get document from cache..."

Is there some sort of permission request needed in some cases? Or some sort of 'defensive' check I need to add before using getDocFromCache()?

I really want to use offline persistence as a cache to prevent unnecessary reads as the user moves around in my app. Thanks in advance!

Answer 1

Sounds like they've got strict tracking prevention mode enabled in Edge (and the equivalent in Chrome).

Have them check (for Edge) Privacy, search, and services -> Tracking Prevention. If it is set to Strict move back to Balanced, also check for Blocked trackers and/or allow an Exception.