Index: src/wp-includes/class-wp-editor.php
===================================================================
--- src/wp-includes/class-wp-editor.php	(revision 38577)
+++ src/wp-includes/class-wp-editor.php	(working copy)
@@ -1257,7 +1257,7 @@
 			var init, id, $wrap;
 
 			if ( typeof tinymce !== 'undefined' ) {
-				// Fix RTL
+				/* Fix RTL */
 				tinymce.on( 'addeditor', function( event ) {
 					event.editor.rtl = event.editor.settings.rtl_ui ||
 						( event.editor.editorManager &&