diff --git a/config/htmlpurifier/Default.json b/config/htmlpurifier/Default.json
index 2aefad8a..7529111b 100644
--- a/config/htmlpurifier/Default.json
+++ b/config/htmlpurifier/Default.json
@@ -7,5 +7,5 @@
     "pagebreak"
   ],
   "HTML.SafeIframe": true,
-  "URI.SafeIframeRegexp": "%^https?://(www.youtube.com/embed/|player.vimeo.com/video/)%"
+  "URI.SafeIframeRegexp": "%^(https?:)?//(www.youtube.com/embed/|player.vimeo.com/video/)%"
 }