Granting admin rights fails for usernames with special characters when admin account has 2FA enabled

[Moin]

@Moin

Side note: Even in the first example where granting admin permissions works, an error appears in the browser console when you click the button:

PUT https://{my-forum}/admin/users/4/grant_admin 403 (Forbidden)

I have learned that this is expected

`run_second_factor!` failing when trying to promote admin

The 403 error is normal and expected — the frontend app catches the 403 response and interprets it as “can’t grant admin because 2FA is required, let’s navigate to the 2FA page”. What is not normal is: Can you tell me where you’re seeing this error? Is it a popup in the frontend? Error in logs? As you mention, I cannot find this error message anywhere in the entire history of the codebase, so it’s very weird.