diff --git a/browser/components/CodeEditor.js b/browser/components/CodeEditor.js
index 64f18e25..fb2f142f 100644
--- a/browser/components/CodeEditor.js
+++ b/browser/components/CodeEditor.js
@@ -381,7 +381,6 @@ export default class CodeEditor extends React.Component {
         'getAnnotations': validatorOfMarkdown,
         'async': true
       },
-      mode: 'markdown',
       gutters: ['CodeMirror-linenumbers', 'CodeMirror-foldgutter', 'CodeMirror-lint-markers'],
       autoCloseBrackets: {
         pairs: this.props.matchingPairs,
diff --git a/lib/main.html b/lib/main.html
index bc7504ad..a8d2761b 100644
--- a/lib/main.html
+++ b/lib/main.html
@@ -127,7 +127,6 @@
   <script src="../node_modules/codemirror/addon/display/rulers.js"></script>
 
   <script src="../node_modules/codemirror/addon/lint/lint.js"></script>
-  <script src="../node_modules/codemirror/mode/markdown/markdown.js"></script>
 
   <script src="../node_modules/raphael/raphael.min.js"></script>
   <script src="../node_modules/flowchart.js/release/flowchart.min.js"></script>