diff --git a/static/viewer.html b/static/viewer.html
index 571bc5780..5d12fadda 100644
--- a/static/viewer.html
+++ b/static/viewer.html
@@ -69,6 +69,7 @@
 
     <iframe id="content_iframe"
             referrerpolicy="same-origin"
+            sandbox="allow-same-origin allow-scripts"
             onload="on_content_load()"
             src="./skin/blank.html?KIWIXCACHEID" title="ZIM content" width="100%"
             style="border:0px">