I made a custom auth provider that accepts the email as username. However, if you try to login to the ACP, you get this error:
You are not able to re-authenticate as a different user.
The problem causing this is in the file includes/functions.php
. When you re-authenticate for the ACP, the provided username is compared with the user data (around line 2358):
// Check if the supplied username is equal to the one stored within the database if re-authenticating