changing (or adding) a new auth login method

[LiquidITGuy]

Description
For now, when we are logged as a google/twitter/github user, we cannot change our auth provider.
If we are changing of company or if the oauth provider is migrated I didn't find any way to change our connexion method to keep our account active.

A clear and concise description of what the new feature is.
A way to add another connexion method or to switch connexion method when we are logged in.

[alexandre-touret]

Hello,
Another example : I'm currently stuck because I have to close my gsuite google account and moving on. I can't change to github authentication for instance.

Regards