Users on Serbian Wikipedia are constantly reporting that Serbian Latin magic words aren't available.
Via VPS-project-Codesearch I found in operations/puppet API query, from which I've removed unnecessary stuff, in order to have an output which is actually needed (see https://sr.wikipedia.org/w/api.php?action=query&meta=siteinfo&siprop=magicwords&format=json&formatversion=2), and it shows me that MediaWiki doesn't even load Serbian Latin magic words, only English + Serbian Cyrillic.
In mediawiki/core (see https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/core/+/refs/heads/master/languages/messages/MessagesSr_ec.php and https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/core/+/refs/heads/master/languages/messages/MessagesSr_el.php) you can see that for Serbian Cyrillic and Serbian Latin, magic words are actually added.
Is there something more that we need to do, in order to have Serbian Latin magic words available as well? I found https://www.mediawiki.org/wiki/Manual:$wgDefaultLanguageVariant, but I don't think that it will work, since we don't want to change the default language variant, but to have Serbian Latin magic words available as well.