If I try to close threads on snapwikiwiki, I get the following error but the thread actually gets deleted-
A database query error has occurred. This may indicate a bug in the software. [6407ea4aeb1174c8b06d3978] 2020-10-30 14:17:14: Fatal exception of type "Wikimedia\Rdbms\DBQueryError"
. However, if I visit the category it was in and check how many threads are in the forum it will show the same count as the previous one before deleting the thread.
I am unable to reproduce this on TestWiki.