CommonSettings has this amusing addition
# Style version appendix # Shouldn't be needed much in 1.17 due to ResourceLoader, but some legacy things still need it $wgStyleVersion .= '-4';
Plus... https://github.com/wikimedia/mediawiki/commit/2d55b1670f34dc63ecc9ce4be20f1b04610d191b - It's been 303 for 6 years
I'm guessing it adds little/no value at this point. And in https://github.com/wikimedia/operations-mediawiki-config/blame/master/wmf-config/CommonSettings.php#L2396 is at at least 6 years too
Is it past time for it to go away now?