diff --git a/www/common/diffMarked.js b/www/common/diffMarked.js
index 07044f5e2..2b2cf4a1c 100644
--- a/www/common/diffMarked.js
+++ b/www/common/diffMarked.js
@@ -84,7 +84,7 @@ define([
 
     var defaultCode = renderer.code;
     renderer.code = function (code, language) {
-        if (language === 'mermaid' && (code.match(/^sequenceDiagram/) || code.match(/^graph/))) {
+        if (language === 'mermaid' && (code.match(/^sequenceDiagram/) || code.match(/^(graph|gantt)/))) {
             return '<pre class="mermaid">'+code+'</pre>';
         } else {
             return defaultCode.apply(renderer, arguments);