The Native Facebook login flow works as follows:
Step 1: The application authenticates a user via the Facebook SDK and acquires an Access Token.
Step 2: The application uses that Access Token to request a special Facebook Session Info Access Token.
Step 3: Use the Facebook SDK to retrieve the users's profile.
Step 4: The application can then use the Facebook Session Info token to authenticate with Auth0.
how does this work in terms of design? instead of using the universal login page, we now have a facebook button, and then another link to the universal login page (except for facebook)?