How can I enable MathJax in chat?

Question

Last updated: 9 May 2017

This is an offshoot of ChatJax, which enables MathJax along with mhchem on chat.

In order to enable MathJax in chat, please follow the following instructions (courtesy of mhchem's answer below):

1. Copy this code into your clipboard

    javascript:(function(){if(window.MathJax===undefined){var script=document.createElement("script");script.type="text/javascript";script.src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS_HTML";var config='MathJax.Ajax.config.path["mhchem"]="https://cdnjs.cloudflare.com/ajax/libs/mathjax-mhchem/3.2.0";MathJax.Hub.Config({extensions: ["tex2jax.js"],tex2jax:{inlineMath:[["$","$"],["\\\\\\\\\\\\(","\\\\\\\\\\\\)"]],displayMath:[["$$","$$"],["\\\\[","\\\\]"]],processEscapes:true},TeX:{extensions:["[mhchem]/mhchem.js","cancel.js"]},jax:["input/TeX","output/HTML-CSS"]});MathJax.Hub.Startup.onload();';if(window.opera){script.innerHTML=config}else{script.text=config}document.getElementsByTagName("head")[0].appendChild(script);window.setInterval(function(){MathJax.Hub.Queue(["Typeset",MathJax.Hub]);},1000);}else{MathJax.Hub.Queue(["Typeset",MathJax.Hub]);}})();

2. Create a bookmark with this (Chrome: Menu > Bookmarks > Bookmark manager > right click > Add page > ...)
3. Whenever you are on a chat page, click the bookmark.

Answer 1

Update 2017-05-01

The MathJax CDN retired and the javascript-URL idea is not so easy any more, because of browser security. (Chrome stips away any leading javascript: when pasting into the URL line. SE modified the javascript: link so that it does not work.)

So here is my take. I modified the script to load the new mhchem (v3), together with cancel (and shortened the URL a little bit).

One-time usage

1. Copy code to clipboard

   (function(){if(window.MathJax===undefined){var script=document.createElement("script");script.type="text/javascript";script.src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS_HTML";var config='MathJax.Ajax.config.path["mhchem"]="https://cdnjs.cloudflare.com/ajax/libs/mathjax-mhchem/3.2.0";MathJax.Hub.Config({extensions: ["tex2jax.js"],tex2jax:{inlineMath:[["$","$"],["\\\\\\\\\\\\(","\\\\\\\\\\\\)"]],displayMath:[["$$","$$"],["\\\\[","\\\\]"]],processEscapes:true},TeX:{extensions:["[mhchem]/mhchem.js","cancel.js"]},jax:["input/TeX","output/HTML-CSS"]});MathJax.Hub.Startup.onload();';if(window.opera){script.innerHTML=config}else{script.text=config}document.getElementsByTagName("head")[0].appendChild(script);window.setInterval(function(){MathJax.Hub.Queue(["Typeset",MathJax.Hub]);},1000);}else{MathJax.Hub.Queue(["Typeset",MathJax.Hub]);}})();
   

2. On chat page, open dev tools (F12 on most browsers)

3. Paste code in console and press ENTER

Use several times

1. Copy this code into your clipboard

   javascript:(function(){if(window.MathJax===undefined){var script=document.createElement("script");script.type="text/javascript";script.src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS_HTML";var config='MathJax.Ajax.config.path["mhchem"]="https://cdnjs.cloudflare.com/ajax/libs/mathjax-mhchem/3.2.0";MathJax.Hub.Config({extensions: ["tex2jax.js"],tex2jax:{inlineMath:[["$","$"],["\\\\\\\\\\\\(","\\\\\\\\\\\\)"]],displayMath:[["$$","$$"],["\\\\[","\\\\]"]],processEscapes:true},TeX:{extensions:["[mhchem]/mhchem.js","cancel.js"]},jax:["input/TeX","output/HTML-CSS"]});MathJax.Hub.Startup.onload();';if(window.opera){script.innerHTML=config}else{script.text=config}document.getElementsByTagName("head")[0].appendChild(script);window.setInterval(function(){MathJax.Hub.Queue(["Typeset",MathJax.Hub]);},1000);}else{MathJax.Hub.Queue(["Typeset",MathJax.Hub]);}})();
   

2. Create a bookmark with this (Chrome: Menu > Bookmarks > Bookmark manager > right click > Add page > ...)

3. Whenever you are on a chat page, click the bookmark.

Answer 2

Based on the same principle, this little bookmarklet loads cancel in addition to mhchem:

javascript:(function(){if(window.MathJax===undefined){var%20script%20=%20document.createElement(%22script%22);script.type%20=%20%22text/javascript%22;script.src%20=%20%22http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS_HTML%22;var%20config%20=%20%27MathJax.Hub.Config({%27%20+%20%27extensions:%20[%22tex2jax.js%22],%27%20+%20%27tex2jax:%20{%20inlineMath:%20[[%22$%22,%22$%22],[%22\\\\\\\\\\\\(%22,%22\\\\\\\\\\\\)%22]],%20displayMath:%20[[%22$$%22,%22$$%22],[%22\\\\[%22,%22\\\\]%22]],%20processEscapes:%20true%20},%27%20+%20%27TeX:%20{%20extensions:%20[%22mhchem.js%22,%22cancel.js%22]%20},%27%20+%20%27jax:%20[%22input/TeX%22,%22output/HTML-CSS%22]%27%20+%20%27});%27%20+%20%27MathJax.Hub.Startup.onload();%27;if%20(window.opera)%20{script.innerHTML%20=%20config}%20else%20{script.text%20=%20config}%20document.getElementsByTagName(%22head%22)[0].appendChild(script);(doChatJax=function(){window.setTimeout(doChatJax,1000);MathJax.Hub.Queue([%22Typeset%22,MathJax.Hub]);})();}else{MathJax.Hub.Queue([%22Typeset%22,MathJax.Hub]);}})();

Start ChatJax with mhchem and cancel

(This also switches to the MathJax distributed network service, http://cdn.mathjax.org/mathjax/latest/MathJax.js)

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