We’ve migrated the Haskell Wiki (https://wiki.haskell.org) to a new server, and along the way updated the version we use of mediawiki. Part of this meant porting our custom wiki skin to work on a newer mediawiki. The new css is still not perfect, and could use some help. If anyone wants to pitch in, the custom skin is in a repo at https://github.com/haskell/haskell-wiki-configuration/tree/master/usr/share/mediawiki/skins/Hawiki
(for the time being, you can still access the old wiki, read-only, for comparison at https://wiki-origin.haskell.org/)