There have been a lot of complaints and bug reports about the state of the $ MathJax $ editing experience all around SE lately. We've heard you, and with a lot of help from the kind folks from $ MathJax $ (a special [shout out](https://gist.github.com/dpvc/c5a3f1be98a7eb342ba1e2da0284c82b/revisions) goes to [Davide](http://math.stackexchange.com/users/7798/davide-cervone)), things are finally moving along.

Today we're rolling out a beta version of the $ MathJax $, PageDown and Markdown integration on meta.math.SE and math.SE, that addresses a bunch of issues. We chose math.SE, because it already proved to be helpful with $ MathJax $ issues in the past (it is the only site that runs on the latest beta.mathjax.org bits).

So please be extra mindful of any $ MathJax $ issues you may encounter in the following days, and please report any bugs here on [meta.math.SE](http://meta.math.stackexchange.com/questions/ask?tags=bug+mathjax).

[![moar mathjax][1]][1]

$P.S.$
Don't forget to disable the editing preview userscripts

$P.S. 2$
Here's a short list of fixes, provided by Davide: 

- disabled the fast preview during editing 
- disabled the assistive MathML during editing 
- processSectionDelay = 0 during editing reduces the flickering and speeds up refreshes slightly 
- disabling the noErrors extension during editing, so that actual error messages appear 
- allow the editor to interrupt MathJax 
- add support for CommonHMTL for the best results
- reset the `\label{}` data before each typeset to prevent multiple-defined label errors

  [1]: https://i.sstatic.net/kNvQt.jpg