diff --git a/helpers/ContentLoader.php b/helpers/ContentLoader.php
index 4b0f488e42..a5abef7ab2 100644
--- a/helpers/ContentLoader.php
+++ b/helpers/ContentLoader.php
@@ -232,7 +232,7 @@ protected function sanitizeContent($content) {
                 "keep_bad"       => 0,
                 "comment"        => 1,
                 "cdata"          => 1,
-                "elements"       => 'div,p,ul,li,a,img,dl,dt,dd,h1,h2,h3,h4,h5,h6,ol,br,table,tr,td,blockquote,pre,ins,del,th,thead,tbody,b,i,strong,em,tt,sub,sup'
+                "elements"       => 'div,p,ul,li,a,img,dl,dt,dd,h1,h2,h3,h4,h5,h6,ol,br,table,tr,td,blockquote,pre,ins,del,th,thead,tbody,b,i,strong,em,tt,sub,sup,s'
             )
         );
     }