Thread:Talk:ResourceLoader/Migration guide for extension developers/Custom skins (2)/reply (3)

I'm not very home in the skins area but from what I know, extensions can extend functionality. This includes Skins.

Historically people provided skins and instructed users to download the skin and put it in the  directory, however I think in the latest version this is no longer supported (if it works, fine, but it's not tested for). Try creating it as an actual extension instead.

btw, what were you trying to reproduce in the comments? I don't see anything..