Board Thread:News and Announcements/@comment-24473195-20150624201317/@comment-11733175-20150721064136

No, global modules do not have the same drawbacks. Wikia has a database that's shared between all wikis, as can be seen from the global user database. It allows them to access the help pages stored on community central anywhere on wikia, and is probably used for the resourceloader modifications that allow interwiki js/css loading. This is what's used to access modules on dev, which is very much different to the template transclusion.

That notice looks to have been added by a bot, with no reference as to why it's been outdated. It might have been an artefact of a mediawiki upgrade (so someone thought it might need checking) or it might be a reflection of the changes in how globals are handled in mediawiki or it might be something else entirely. Since wikia is now 6-7 version behind the developed version of mediawiki I would guess it's still pretty accurate for our purposes.