Board Thread:Support Requests - Designing Your Wiki/@comment-34631921-20200526210606/@comment-168424-20200527173120

Okay, so you used two different wikis with links... the first one was pre-UCP and the 2nd is a UCP wiki. The source editor in UCP has all sorts of problems, so I would just report it via (mention it is a UCP wiki and include your screenshot) "Contact us". I saw your problem, but it wasn't quite as bad on my browser for some reason.

The CSS that is causing the problem should not take effect upstream of the source editor, if it were designed right.

I will add your bug to User:Noreplyz/UCP.

FYI, pre-UCP wikis and UCP wikis behave radically differently in many cases.