diff --git a/lib/javascript-static.js b/lib/javascript-static.js
index 96284a9b5c9..38a4dd82d2d 100644
--- a/lib/javascript-static.js
+++ b/lib/javascript-static.js
@@ -332,7 +332,11 @@ M.util.init_maximised_embed = function(Y, id) {
             if (val == 'auto') {
                 val = el.getComputedStyle(prop);
             }
-            return parseInt(val);
+            val = parseInt(val);
+            if (isNaN(val)) {
+                return 0;
+            }
+            return val;
         } else {
             return 0;
         }