diff --git a/wp-includes/js/tinymce/langs/wp-langs.php b/wp-includes/js/tinymce/langs/wp-langs.php
index f9586d600e..fa416303c1 100644
--- a/wp-includes/js/tinymce/langs/wp-langs.php
+++ b/wp-includes/js/tinymce/langs/wp-langs.php
@@ -3,6 +3,9 @@
 if ( ! defined( 'ABSPATH' ) )
 	exit;
 
+if ( ! class_exists( '_WP_Editors' ) )
+	require( ABSPATH . WPINC . '/class-wp-editor.php' );
+
 // deprecated, not used
 function mce_escape($text) {
 	return esc_js($text);