diff --git a/_build/format_header.html.erb b/_build/format_header.html.erb
index 525fc5669..b9ba10890 100644
--- a/_build/format_header.html.erb
+++ b/_build/format_header.html.erb
@@ -22,7 +22,7 @@
 
         <div class="row">
             <div class="col-md-8">
-                <p><%= CommonMarker.render_html(yaml['doc']) if yaml['doc'] %></p>
+                <p><%= Commonmarker.to_html(yaml['doc']) if yaml['doc'] %></p>
             </div>
             <div class="col-md-4">
                 <div class="panel panel-info">