Just noticed the above.
See Use Firebase - Expo Documentation
It links to expo.fyi/firebase-migration-guide
As it says in the Expo SDK 47 release blog post:
- expo-firebase- libraries are deprecated*. If you use
expo-firebase-analytics
orexpo-firebase-recaptcha
in your app, we suggest migrating to React Native Firebase. Refer to the “Migrating from Expo Firebase to React Native Firebase” guide for more information.