I've been thinking about it and think we should show the temporary user and still show the message that they cannot be added to intro groups, the same way we see messages that users do not exist or maybe there's a spelling mistake.

Removing them altogether from the search/dropdown, might be leading to thinking the temp users do not exist and create confusion.

What do you think @Dreamy_Jazz @Niharika

If it helps, we have a task for allowing the input to be configurable, e.g. to exclude temporary users: T332030: Update user name widgets config to accept or deny temporary user names, which I think we should do regardless of what we decide here.

I think my preference would be to exclude temporary users here, since it's less noisy and I think the message would be clear that they're excluded from groups. But I see your argument @AGueyte, and I'm interested to hear what the others think.

I don't have a strong opinion either way, however, some thoughts:

• When someone uses this form to give or remove groups, they should know the username in advance
• When someone uses the form to view the groups of a user, they should also know the username in advance

As such, the suggestions list is in most cases simply an auto fill and not a way to find an account. As such, if the person wanting to manage groups for a temporary user uses the form they will know in advance the username and it not appearing won't necessary give them the information that users cannot have a group.

On the other hand, the autocomplete suggesting a temporary user may give the impression that it is possible to assign rights (even if this requires changing a configuration value in LocalSettings.php to achieve).

I agree with @Tchanders - including temp users in this dropdown does not make any value addition for the end user since temporary accounts cannot be added to groups. Once a user starts typing "* Unr....." they will immediate know that temp users are not a valid entry if we don't autocomplete, thus saving them the bother of finding the right user and trying to assign them rights.

Change 953498 had a related patch set uploaded (by AGueyte; author: AGueyte):

[mediawiki/core@master] WIP: Update Special:UserRights form to exclude Temp users

https://gerrit.wikimedia.org/r/953498

Moving to the backlog while other work is prioritised

Change #953498 merged by jenkins-bot:

[mediawiki/core@master] Update Special:UserRights form to exclude temporary users

https://gerrit.wikimedia.org/r/953498

QA has been completed, and the new code change(s) are functioning as expected (temporary users are not auto-filled/auto-completed in the textfield on Special:UserRights page).