MathJax 2.3 has broken IE 6-8 compatibility (v2.2 works)

Created by: thomastan

I've been loading the "latest" from the CDN:

<script src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=Accessible">
  MathJax.Hub.Config({
    jax: ["input/TeX", "output/HTML-CSS"],
    tex2jax: { inlineMath: [['$','$']], displayMath: [['$$','$$']] },
    TeX: { equationNumbers: { autoNumber: "AMS" } },
    "HTML-CSS": { availableFonts: ["TeX"] }
  });
</script>

Since v2.3 replaced 2.2, I'm getting the following break on IE 6-8 (IE 9+ works fine, for v2.2 all IE versions were good):

Line: 58 Char: 418 Error: JScript object expected Code: 0 URL: http://cdn.mathjax.org/mathjax/latest/config/Accessible.js

Of course, using "http://cdn.mathjax.org/mathjax/2.2-latest/MathJax.js?config=Accessible" works, but I'd rather MathJax be fixed than have to revert to a previous version.