Hello guys, can I use Firebase Auth as Identity provider to implement the Login flow with Hydra? The idea would be to authenticate the user with firebase client side. That generate a JWT token and I would use the same JWT token server side to authorise hydra challenge login request (NextJs). I would like to use Firebase Auth directly for first-party login and reuse the JWT token for the oauth requests coming from Hydra. Does it sounds like a viable option? Anybody integrated Hydra with Firebase Auth?

I was using Identity Platform (Firebase Auth) in a web app that served as the IdP for Hydra, but I can't say I understand why you would need Hydra if you're going to use Firebase Auth (which issues and handles ID and refresh tokens) on clients

My first-party web app user data are stored on Firebase. Now I want to let third party web apps to implement a “Login with my App”, so users that already have an account on my Firebase Auth backend can log in. As far as I can tell I cannot do that with Firebase Auth alone and I need something like Hydra to become an OpenID connect provider.

I think you need to build and host a new web app that uses the client Firebase Auth SDK for login. On the server you can handle the admin API calls to Hydra (accept/reject login and accept/reject consent). We were doing that for a while at my company (using Google Cloud Identity Platform) and are now migrating to Ory Kratos, but it can be done. 👍