[cybrix12]

Does it mean that a single user can be bound to more then one User Federation/Identity Provider?

Can you provide more detail on how you've done this?

[snuxoll]

Keycloak links federated identities to its own user accounts, users can do this manually from the account management UI or it can automatically link them by email when a user signs in with a new IdP.

No configuration beyond setting up the federated provider required.