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Area

admin/ui

Describe the bug

When usernames (from UserStorage SPIs) containing the '#' character cause errors in the Keycloak admin console when attempting to assign roles.
Specifically, the user ID is truncated at the '#' character, leading to a "User not found" error.

Version

main

Regression

[ ] The issue is a regression

Expected behavior

UI should escape the special char and handle the request

Actual behavior

"User not found" error

How to Reproduce?

Use a custom User Storage SPI i.e from quickstarts
Edit the users.properties file to include a user with special characters (e.g. test2#y400)
Find the user in admin console users page and click on it to see user's details
Navigate to Role mapping tab
Uncheck the "Hide inherited roles" box.
see the UI error

Anything else?

No response