revert mathjax script

common/templates/_footer.html

@@ -48,25 +48,3 @@
     }, 0);
   });
 </script>
-<script>
-  MathJax = {
-    tex: {
-      inlineMath: [['\(', '\)'],['$','$']],
-      displayMath: [['$$','$$']],
-      processEscapes: true,
-      processEnvironments: true,
-      tags: 'ams'
-    },
-    options: {
-      skipHtmlTags: ['script', 'noscript', 'style', 'textarea', 'pre']
-    },
-    chtml: {
-       mtextInheritFont: false,
-       matchFontHeight: false
-    },
-    loader: {
-      load: ['ui/lazy']
-    }
-  };
-</script>
-<script id="MathJax-script" async src="/mathjax/tex-chtml.js"></script>