diff --git a/lib/outputrequirementslib.php b/lib/outputrequirementslib.php
index b5d57335a69..458e5727886 100644
--- a/lib/outputrequirementslib.php
+++ b/lib/outputrequirementslib.php
@@ -347,7 +347,7 @@ class page_requirements_manager {
                 case 'core_filepicker':
                     $module = array('name'     => 'core_filepicker',
                                     'fullpath' => '/repository/filepicker.js',
-                                    'requires' => array('base', 'node', 'json', 'async-queue', 'io', 'yui2-button', 'yui2-container', 'yui2-layout', 'yui2-menu', 'yui2-treeview'),
+                                    'requires' => array('base', 'node', 'json', 'async-queue', 'io', 'yui2-button', 'yui2-container', 'yui2-layout', 'yui2-menu', 'yui2-treeview', 'yui2-dragdrop'),
                                     'strings'  => array(array('add', 'repository'), array('back', 'repository'), array('cancel', 'moodle'), array('close', 'repository'),
                                                         array('cleancache', 'repository'), array('copying', 'repository'), array('date', 'repository'), array('downloadsucc', 'repository'),
                                                         array('emptylist', 'repository'), array('error', 'repository'), array('federatedsearch', 'repository'),