I've been installing a local copy of MediaWiki with the Math extension and MathJax enabled. Looking at the preferences Special:Preferences#mw-prefsection-rendering the MathJax option appears twice: once as radio button and once as a check box.

I've a clean install using

git clone https://gerrit.wikimedia.org/r/p/mediawiki/extensions/Math.git

and a git clone of the latest mediawiki.

my LocalSettings.php is pretty much copied direct from https://www.mediawiki.org/wiki/Extension:Math

require_once( "$IP/extensions/Math/Math.php" );

* Set this if you don't use MediaWiki Math's texvc:
* $wgTexvc = '/your/path/to/texvc';

* Be sure to have a math directory with writing
* permission and that these two variables are set or

// default to that directory:

$wgMathDirectory = $wgScriptPath . '/mathCache';

$wgMathPath = 'http://localhost/~rich/mediawiki/mathCache';

$wgMathValidModes[] = MW_MATH_MATHJAX; * adding MathJax as rendering option
* or

*$wgMathValidModes = array( MW_MATH_MATHJAX );*setting MathJax as only rendering option (optional)

$wgUseMathJax = true; * enabeling MathJax as rendering option
$wgDefaultUserOptions['mathJax'] = true; * setting MathJax as default rendering option (optional)

I think this may relate to

https://gerrit.wikimedia.org/r/#/c/127607/

Also if I change the rendering options to

*$wgMathValidModes[] = MW_MATH_MATHJAX; * adding MathJax as rendering option

* or
$wgMathValidModes = array( MW_MATH_MATHJAX ); * setting MathJax as only rendering option (optional)

I get [b768f98f] 2014-05-04 19:11:43: Fatal exception of type MWException when trying to view my preferences

**Version**: REL1_23-branch

**Severity**: normal