diff --git a/lib/yui/chooserdialogue/chooserdialogue.js b/lib/yui/chooserdialogue/chooserdialogue.js
index fbbb1ce754a..cad6f1f0b54 100644
--- a/lib/yui/chooserdialogue/chooserdialogue.js
+++ b/lib/yui/chooserdialogue/chooserdialogue.js
@@ -31,7 +31,7 @@ YUI.add('moodle-core-chooserdialogue', function(Y) {
         },
 
         prepare_chooser : function () {
-            if (this.overlay) {
+            if (this.panel) {
                 return;
             }