Since January we have not been serving traffic to browsers which don't support TLS 1.2 (T238038).
It doesn't really make sense to maintain Grade C support just for third party wikis that might be using very old browsers. Third parties can continue to use MediaWiki 1.35 (LTS).
As mentioned in T262946#6512792, this means increasing our requirements to:
* Firefox 24+ (released 2014-02, Firefox v24 of 2013-08 – v26 can be enabled too, 27+ by default)
* Chrome 29+ (2013-07)
* Safari 7+ (2013-10, also grade A)
* Opera 16+ (2013-08)
* iOS Safari 5 (2012-03, already grade C)
* Android browser 5-6x ([[ https://en.wikipedia.org/wiki/Google_Chrome#Platforms | Chromium 81 WebView ]]) or Google Chrome for Android or other browsers like Firefox Android
IE 9-10 would be untouched by this, as both versions can be enabled to support TLS 1.2.
Opera 12 would have been able to support it too, but has already fallen out of basic support.
**[[https://www.mediawiki.org/wiki/Compatibility#Browser_support_matrix|Current browser support matrix]]**