Affected components: MediaWiki core, all skins/extensions, Wikimedia Foundation product, third-parties.
Android up to 4.4.4 is currently responsible for many of the remaining -webkit- vendor prefixed properties in render critical CSS, for example on transition property. (Chrome up to 42 is the other one,
but that's more neglible as it's non-existent in our access stats with Chrome 38 as somewhat significant outlier with up to 0.5% of pageviews 2021 according to analytics.wikimedia.org)
Turnilo breakdown (login only) of OS family, major and minor versions for last 30d, showing Android 4.2 leading, 4.4 behind, 4.3 and others basically non-existing. Altogether at widely under 1%.
Possible alternative to proceed on
Focus on CSS only and remove -webkit- vendor properties and leave JS support, browserslist-config-wikimedia and infrastructure access untouched.