Does secondary app support messaging and crashlytics?

[sergeymorkovkin]

It's not clear, since there is a lot of contradicting information.

1. No information in official docs - https://rnfirebase.io/app/usage#secondary-apps

2. Can expose initializeApp? #3337

Mar 25, 2020 - Those modules don't support secondary apps sorry, that's a Firebase SDK limitation.
Mar 26, 2020 - That's not possible with the native SDKs I'm afraid.

So, not possible?

3. Messaging from secondary firebase app #1864 (comment)

Jan 30, 2020 - I'm going to close this PR for now as stale, this functionality exists on v6 also.

So, it exists?

[sergeymorkovkin]

Answered here:
https://stackoverflow.com/questions/62253691/firebasemessaging-getinstancefirebaseapp-for-secondary-app-supposed-to-be-publ

[mikehardy]

Officially not supported per that excellent link:

Answer regarding separate projects for FCM and Crashlytics:

Upon discussing with the team, they’ve verified that your use case is not supported by Firebase. You should be using a single Firebase Project/Firebase App for both FCM and Crashlytics. Thanks for understanding.