The only forum setting I am aware of that may be different from a admin and users may be , allow ubbcode and allow html for posts.
It is not recommended to allow html posts for anyone.
But usually everyone allows users UBB Code posts.
While waiting what I would do is first goto phpmyadmin and make sure every table is set to utf8mb4_general_ci and the database is set to utf8mb4_general_ci.
And report back if at least any of that was incorrect.
But don't change anything yet.
To make the tool run again it is just a couple of simple clicks on UBB cp but I refrain from saying so till you hear from the experts.
