Update ext.SimpleMathJax.js

resources/ext.SimpleMathJax.js

@@ -1,3 +1,4 @@
+mw.hook( 'wikipage.categories' ).add( function ( $content ) {
 window.MathJax = {
   tex: {
     inlineMath: mw.config.get('wgSmjExtraInlineMath').concat([['[math]','[/math]']]),
@@ -130,3 +131,4 @@ window.MathJax = {
   script.async = true;
   document.head.appendChild(script);
 })();
+});