Index: _source/plugins/filebrowser/plugin.js
===================================================================
--- _source/plugins/filebrowser/plugin.js	(revision 4918)
+++ _source/plugins/filebrowser/plugin.js	(working copy)
@@ -348,6 +348,9 @@
 		if ( targetInput )
 			dialog.getContentElement( targetInput[ 0 ], targetInput[ 1 ] ).reset();
 
+		if ( typeof data == 'function' && data.call( this._.filebrowserSe ) === false )
+			return;
+
 		if ( onSelect && onSelect.call( this._.filebrowserSe, fileUrl, data ) === false )
 			return;