diff --git a/lib/javascript-static.js b/lib/javascript-static.js
index 6bf2e28bbe1..5640b44247f 100644
--- a/lib/javascript-static.js
+++ b/lib/javascript-static.js
@@ -1779,6 +1779,7 @@ M.util.load_flowplayer = function() {
                     // why??
                     continue;
                 }
+                if (!allrules) continue;
                 for(var i=0; i<allrules.length; i++) {
                     rule = '';
                     if (/^\.mp3flowplayer_.*Color$/.test(allrules[i].selectorText)) {