Fixed, thanks for the report!

With MediaWiki 1.35 deployed to production, the fix for this issue should be included and the "report a problem" dialog should be working as expected again, so closing this task.

The arguments for open source are very compelling, and in case if you're not familiar with our open source work, there's a lot of it: Category:Extensions by ShoutWiki on MediaWiki.org covers some of it, but I want to clarify a few things here for the record...

Yay weird PHP8-specific bugs.

Closing due to a lack of further info from the reporter.

Is this problem still occurring? I just tested logging in on ShoutWiki Hub and I had no issues with logging in/logging out/logging back in.

This was fixed on the same day by @lewiscawte (kudos!). The mistake was mine, sorry about that; I was trying to stop some cross-wiki spam originating from a certain IP range and as the spam edits (but not account creations) stopped, I figured the code snippet worked as expected, but I didn't test it. Again, apologies for this!

That was a fun one to fix. The upgrade script hadn't run for it because its DB had been locked due to excessive spam. The DB locking had been done via [[Special:LockDB]] rather than by setting $wgReadOnly in the wiki's settings file, so I had to move the lockfile temporarily out of the way in order to be able to run update.php.