The title.
Topic on MediaWiki talk:Common.js
It's an unfortunate side effect of containing the various template definitions for editor buttons.
So it's not possible to fix or workaround it somehow? Not a big deal, but pretty silly.
Issues like this should be solved since back in July of this year, following this change: https://www.pcgamingwiki.com/w/index.php?title=MediaWiki%3ACommon.js&type=revision&diff=829973&oldid=829906
Better late than never I guess 👍