MediaWiki core includes a "Fallback" skin. It's what you see if somehow wgDefaultSkin isn't available. It isn't visible to users. (Try it by adding ?useskin=fallback to a page, see for example: https://www.mediawiki.org/wiki/MediaWiki?useskin=fallback
Because SkinFallback is in MediaWiki core (see the code search results), it shows up in Doxygen's class diagrams that are otherwise helpful for class Skin, but the generated documentation for SkinFallback is terrible.
It only needs a few changes:
- merge the two comment blocks at the top of these files
- add the explanation I gave above
- improve the confusing overlapping statements
- "Skin template for the fallback skin
- "SkinTemplate class for the fallback skin
I don't think the files should be marked \@ingroup Skins since it's not relevant to other skins.