diff --git a/app/pages/index.jsx b/app/pages/index.jsx
index ebc89ba..1ca7223 100644
--- a/app/pages/index.jsx
+++ b/app/pages/index.jsx
@@ -9,6 +9,7 @@ import footnote from 'markdown-it-footnote'
 import markdownItAnchor from 'markdown-it-anchor'
 import markdownItToc from 'markdown-it-toc-done-right'
 import markdownDeflist from 'markdown-it-deflist'
+import markdownMakr from 'markdown-it-mark'
 
 import mk from './katex'
 import chart from './chart'
@@ -214,6 +215,7 @@ export default class PreviewPage extends React.Component {
         .use(emoji)
         .use(taskLists)
         .use(markdownDeflist)
+        .use(markdownMark)
         .use(footnote)
         .use(image)
         .use(markdownImSize)