Canasta is a MediaWiki-based Docker image:
https://github.com/WikiWorks/Canasta
Its Dockerfile does a variety of things, one of which is to add the line "#cfLoadSkin()" to LocalSettings.php for every skin that is included in Canasta:
https://github.com/WikiWorks/Canasta/blob/master/Dockerfile
In other words, it adds commented-out lines, so that the admin can include them if they want to. This is fine - but one skin, Vector, should be included by default, i.e., not start with "#".
This is a Google-Summer-of-Code 2022 microtask for T301893.