Index: wp-includes/class-wp-editor.php
===================================================================
--- wp-includes/class-wp-editor.php	(revision 46439)
+++ wp-includes/class-wp-editor.php	(working copy)
@@ -436,7 +436,7 @@
 					 *
 					 * @param array $plugins An array of default TinyMCE plugins.
 					 */
-					$plugins = array_unique( apply_filters( 'tiny_mce_plugins', $plugins ) );
+					$plugins = array_unique( apply_filters( 'tiny_mce_plugins', $plugins, $editor_id ) );
 
 					$key = array_search( 'spellchecker', $plugins );
 					if ( false !== $key ) {