dbanet

// ==UserScript==
// @name        Force old MathJax version on MSE
// @namespace   https://gist.github.com/dbanet
// @description Please make sure you use AdBlock to blacklist ``*beta.mathjax.org/mathjax/latest/MathJax.js*''
// @include     *math.stackexchange.com*
// ==/UserScript==

script=document.createElement("script");
script.src="//cdn.mathjax.org/mathjax/2.5-latest/MathJax.js?config=TeX-AMS_HTML-full";
document.head.appendChild(script);