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ChatJax++, a user script to enable MathJax in Stack Exchange chat
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ChatJax++ is a user script to enable MathJax in Stack Exchange chat. It aims to be an easier, faster and more lightweight alternative to RobJohn's ChatJax bookmarklets.

Some notable features of ChatJax++ include:

  • As a user script, ChatJax++ runs automatically when you open chat. There's no need to click a separate bookmark to turn on MathJax.
  • ChatJax++ only runs in chat rooms belonging to sites that use MathJax. Thus, you don't need to worry about text in other chat rooms getting messed up. Also, text from other rooms shown in the sidebar will not be parsed for MathJax.
  • ChatJax++ automatically loads the MathJax settings from the site the chat room belongs to. Thus, for example, the mhchem extension is automatically enabled for the Chemistry and Biology chats, and alternative \$ delimiters are automatically used for Electrical Engineering and Code Review.
  • Instead of continually re-processing the whole page, ChatJax++ dynamically processes new chat messages as they arrive. This should make ChatJax++ more responsive, and minimize its CPU load. If you like, you can easily have dozens of chat tabs open at the same time, with ChatJax++ running in all of them.

Note that ChatJax++ is still under development. Some issues to be fixed before v1.0 include:

  • There is currently no way to manually enable or disable MathJax in a particular chat room (except by marking the room's URL as excluded in your user script manager).
  • There's a possible race condition, where messages that you post yourself may sometimes not display MathJax correctly. Unfortunately, reliably reproducing this issue seems tricky. This may have been fixed by ChatJax++ v0.3, but I can't be 100% sure of it.

Users with Greasemonkey (Firefox) or Tampermonkey (Chrome and other browsers) installed may install this user script by clicking this link.

While ChatJax++ has currently only been tested on Firefox + Greasemonkey and Chrome + Tampermonkey, it will probably work on other similar browsers like Opera. Compatibility with Microsoft Edge has not been tested, and there's a pretty good chance that something won't work. If you can test it, please let me know if it works or not. When reporting issues, please try to include any diagnostic output (especially any lines starting with "ChatJax++ error") printed to the browser's Developer Tools console; this will make anylyzing and reproducing the issue much easier.

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