T67306 completely breaks Pywikibot's use on WMF wikis as we don't except other static characters around the wmf suffix. So the MediaWikiVersion handler considers it “another” style but it asserts that none of the handled strings appear in the “other” style (as it indicates that something was missed).

The parsing exists primarily to determine whether it is a pre-release version, or a post release suffix added by distributions.

However as Pywikibot also runs automated tests on beta cluster and test sites, the code occasionally needs to check for specific deploy branches before enabling a feature.