I've had this question a few times during situations with the train where there's an issue with a specific extension.
Some useful IRC backscroll:
17:33 <brennen> question i keep having and not knowing the answer to: what's the quick way to cross reference groups with what extensions are enabled? 17:37 <AntiComposite> "quick way" 17:37 <bd808> Not sure that there is one 17:37 <legoktm[m]> ctrl+f for "wmgUse" in InitialiseSettings :| 17:38 <mutante> wikiapiary kind of knows where each extension is ued 17:38 <mutante> example https://wikiapiary.com/wiki/Extension:Babel 17:38 <mutante> at the bottom there is "Wikibooks (fa)" but amont all other mediawikis out there 17:38 <mutante> among 17:38 <AntiComposite> yeah, cross-referencing CommonSettings.php and InitialiseSettings.php is the best I've got 17:40 <mutante> wikiapiary links are from "check usage and version matrix" link in the infobox on an extension page like https://www.mediawiki.org/wiki/Extension:RSS 17:40 <AntiComposite> one of the "rethink MediaWiki/Wikimedia configuration" phab tasks may eventually result in a better solution
Ideally, I'd like to just give something an extension name and have it say what groups it's deployed in. Might be less relevant in a Kubernetes future, but would certainly be useful at the moment.