Registration fails when other user was logged in before

I’d like to display a registration button in our application even when a user (user1) is logged in.

Directly calling the registration form seems to be supported according to
However, the login after the registration (of user2) fails when user1 was logged in before.
The problem can be reproduced by following these steps:

  1. Log user1 into the account app
  2. Open the registration form at https://<host>/auth/realms//protocol/openid-connect/registrations?client_id=account&response_type=code&scope=openid+email&redirect_uri=<url_to_account_app>
  3. Register user2
  4. After registration, this message is shown: “We’re sorry… You are already authenticated as different user in this session. Please logout first.” The message contains a link “Back to Application”.

However, user1 is not logged in anymore and the link “Back to Application” leads to the login form.
This situation is not straightforward for a user to resolve: user1 has to log in again, then log out, and only then is user2 able to log in.

The reason appears to be that opening the registration form in step 2 deletes the cookies KEYCLOAK_IDENTITY and KEYCLOAK_SESSION. However, the cookie AUTH_SESSION_ID remains unchanged. To me it seems that opening the registration form should cause a new AUTH_SESSION_ID to be generated (beside KEYCLOAK_IDENTITY and KEYCLOAK_SESSION being cleared). I’d appreciate any thoughts on that!


For those of you who still struggle with this issue, what you can do is navigate user to the logout url first and then redirect to registration form using redirect_uri query param. So your url should look like:
Obviously you need to encode registration url so it can be used as query param.