How are we supposed to use the new API and their Oauth 2.0 tokens with the Unity SDK?
Currently, using Unity SDK and the legacy messaging API, we can simply call a method to get the authentication token, and then use it when sending messages to
https://fcm.googleapis.com/fcm/send.
I am at a loss on how to implement this new API. There is no documentation on how to integrate it with Firebase Unity SDK.