Is Firebase Library ready to use?

Questions & Answers
1

Official Unity Firebase GitHub - googlearchive/Firebase-Unity

It didn’t show on the official site’s SDK. Here : Firebase Documentation

  1. Is Unity’s Firebase Library ready to use?
  2. What features were missing?
  3. What’s difference between Unity Asset Store - The Best Assets for Game Making and official SDK
2

That Unity Plugin not support the last version of firebase.
if you are using firebase analytic,you can try

https://github.com/unity-plugins/google-play-game-service-unity-plugin