Last modified: 2014-01-25 15:37:24 UTC
Code in the module namespace is highlighted with Geshi (at least on wmf wikis), but the local MediaWiki:Geshi.css is not loaded, so local changes there for the lua language have no effects to the highlighting.
Why does SyntaxHighlight_GeSHi::buildHeadItem() not handle this, I wonder, considering that it handles the rest of the GeSHi CSS bits. Or else SyntaxHighlight_GeSHi should provide another static method to handle it, so other extensions don't have to know about SyntaxHighlight_GeSHi's ResourceLoader modules and whatever checks it does to decide when to load it.