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Area

authentication

Describe the bug

When registration is active or there is an org invite, if I have set email as username to true:
<img width="327" alt="image" src="https://github.com/user-attachments/assets/2cc6a615-96df-438f-ba4f-d837a7095cf8">

And I also have set that users are not able to edit their emails:
<img width="1166" alt="image" src="https://github.com/user-attachments/assets/568274fa-9dcc-4cc5-8481-7bf151deb5c0">

Then the registration screen is incomplete and users are not able to register:
<img width="835" alt="image" src="https://github.com/user-attachments/assets/c9a3109d-cd3a-41cc-862d-95d97c2cd36f">

Version

nightly

Regression

[ ] The issue is a regression

Expected behavior

I would expect that user registration is not tied to the setting I set for users in the realm allowing them to register without issues even if their username is the email and the email is not editable once registered.

Also, for invitation to an organization I would expect that if an email is already set, then the rule that they cannot edit it is enforced.

Actual behavior

Setting email as username and removing the ability to edit the email breaks the registration process (both when registration is enabled and on org invite)

How to Reproduce?

Activate registration or send an org invite to a non existent user.

Activate email as username:
<img width="327" alt="image" src="https://github.com/user-attachments/assets/2cc6a615-96df-438f-ba4f-d837a7095cf8">

Remove the ability to edit emails for users:
<img width="1166" alt="image" src="https://github.com/user-attachments/assets/568274fa-9dcc-4cc5-8481-7bf151deb5c0">

Go to the registration screen and see that it is incomplete.

Anything else?

A similar issue was reported and closed a few version ago, when the user profile was not a fully supported feature:
https://github.com/keycloak/keycloak/issues/17439