Unable to get id_token for firebase customSignIn

Was going through a blog about making auth0 and firebase work together. for keeping the firestore secured on the backend, authentication through firebase auth is a must. for that there’s a method of createCustomToken(token) signInWithCustomToken(token) for signing in firebase. and that token is the id_token provided by auth0 while authenticating via it.
The blog instructed to get that id_token. So how do you get that?

Thanks, help would be highly appreciated
plus updating the existing blog about it would be helpful too :slight_smile:

You need to request the openid scope to get an id token.