Ask the user for an email if it's not present in Facebook profile

Hi, we have the next problem. Having email is essential for our application.
We have the facebook social connection, with checkbox Settings -> User Data -> Email is checked. So when users create auth0 account linked to facebook, the primary email is copied to auth0 profile, and this is OK.

The issue happens, when facebook account doesn’t have email, i.e. when it linked to a phone number.
In this case, auth0 account is created with “email_verified”: true, but actually, without email.
For us, such account is broken, we can’t live without email. So we have added the rule, which forbids to login if email is not present.
But for us will be much better, that instead of such a rule, to prompt the user to enter email, and then verify it by auth0. Is it possible to achieve such a behaviour?

(maybe it somehow related to Auth0 facebook login email issue)

The Progressive Profiling approach would be the way to go (initiated from a Rule, as shown in the docs), see:

The dialog that asks the user for the email address would be a custom one hosted on your end (not something Auth0 provides out of the box), where the Rule redirects to, which then returns back to the Auth0 authentication flow once the user has entered his email.

It’s a pity. Because in db connection auth0 already has functionality to ask and verify email. In this case it looks very similar, but we should reinvent the wheel and do the same on our side, it’s strange…