Detecting social login exits already

By way of introduction, I first asked a question on the forum here -Detecting social login exists from auth0 JS library
I was instructed to post a feature request to Github. The person then recommend that I raise a request here.

Feature:
Add the ability to detect if a social login has been performed already as part of authorization.

Description:
My login page in the Universal Login uses both sign up and sign in functionality for social and username/password logins. I use the auth0.WebAuth() library and webAuth.authorize() for google or facebook.

On the sign up form I have a checkbox to enforce the user checks the terms & conditions. I don’t want to have this same checkbox on the signin form. However, the problem is that a user can simply bypass the signup option and sign in with Google and facebook.

Use-case: The idea is to perform custom steps before a user signs up or signs into a system for the first time. Using just webAuth.authorize() for google or facebook, I’m unable to determine if the user has signed in before.

Hey there!

Thank you for creating this feedback card. Let’s see who is interested in such improvement as well!