diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index c3d89eb1b8..ce1d0538b8 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -222,6 +222,8 @@ module ApplicationHelper
 
   def render_markup(file_name, file_content)
     GitHub::Markup.render(file_name, file_content).html_safe
+  rescue RuntimeError
+    simple_format(file_content)
   end
 
   def spinner(text = nil, visible = false)