MyBB Community Forums

Version affected: 1.8.22
Reproduction steps: visit https://community.mybb.com/online.php?sortby=username

Culprit: https://github.com/mybb/mybb/blob/featur...e.php#L131

Changing u.username to username gets rid of the error, but I haven't tested if it actually restores the functionality.

^ Thank You for reporting

Fixed in https://github.com/mybb/mybb/issues/3874

Thanks, couldn't find it.