From 8bbb5869e99328a7eb9838e01c8c1eea14bd2fbb Mon Sep 17 00:00:00 2001
From: Andrew Ozz <azaozz@git.wordpress.org>
Date: Tue, 24 Mar 2015 20:32:23 +0000
Subject: [PATCH] TinyMCE: fix error and PHP warning when adding more than one
 instance in RTL mode. Part props maimairel. Fixes #31578.

git-svn-id: https://develop.svn.wordpress.org/trunk@31874 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/functions.php | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/wp-includes/functions.php b/src/wp-includes/functions.php
index 9c24d0b34d..0e5600e7b2 100644
--- a/src/wp-includes/functions.php
+++ b/src/wp-includes/functions.php
@@ -2906,8 +2906,14 @@ function _config_wp_siteurl( $url = '' ) {
 function _mce_set_direction( $input ) {
 	if ( is_rtl() ) {
 		$input['directionality'] = 'rtl';
-		$input['plugins'] .= ',directionality';
-		$input['toolbar1'] .= ',ltr';
+
+		if ( ! empty( $input['plugins'] ) && strpos( $input['plugins'], 'directionality' ) === false ) {
+			$input['plugins'] .= ',directionality';
+		}
+
+		if ( ! empty( $input['toolbar1'] ) && ! preg_match( '/\bltr\b/', $input['toolbar1'] ) ) {
+			$input['toolbar1'] .= ',ltr';
+		}
 	}
 
 	return $input;