From 2ebdfc16eb962975a973cefbd1e5ee7504713196 Mon Sep 17 00:00:00 2001
From: Andrew Ozz <azaozz@git.wordpress.org>
Date: Sat, 10 Jul 2021 23:57:43 +0000
Subject: [PATCH] TinyMCE: ensure initialization runs in all cases on
 'interactive' and 'complete' readyState. Fixes a rare bug when the init code
 is inserted in the DOM after the page has finished loading.

Props Collizo4sky, azaozz.
Fixes #53632.

git-svn-id: https://develop.svn.wordpress.org/trunk@51402 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/class-wp-editor.php | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/wp-includes/class-wp-editor.php b/src/wp-includes/class-wp-editor.php
index 914613508e..61cda16585 100644
--- a/src/wp-includes/class-wp-editor.php
+++ b/src/wp-includes/class-wp-editor.php
@@ -1663,7 +1663,8 @@ final class _WP_Editors {
 		?>
 
 		( function() {
-			var initialize = function() {
+			var initialized = [];
+			var initialize  = function() {
 				var init, id, inPostbox, $wrap;
 				var readyState = document.readyState;
 
@@ -1672,6 +1673,10 @@ final class _WP_Editors {
 				}
 
 				for ( id in tinyMCEPreInit.mceInit ) {
+					if ( initialized.indexOf( id ) > -1 ) {
+						continue;
+					}
+
 					init      = tinyMCEPreInit.mceInit[id];
 					$wrap     = tinymce.$( '#wp-' + id + '-wrap' );
 					inPostbox = $wrap.parents( '.postbox' ).length > 0;
@@ -1679,9 +1684,10 @@ final class _WP_Editors {
 					if (
 						! init.wp_skip_init &&
 						( $wrap.hasClass( 'tmce-active' ) || ! tinyMCEPreInit.qtInit.hasOwnProperty( id ) ) &&
-						( ( inPostbox && readyState === 'complete' ) || ( ! inPostbox && readyState === 'interactive' ) )
+						( readyState === 'complete' || ( ! inPostbox && readyState === 'interactive' ) )
 					) {
 						tinymce.init( init );
+						initialized.push( id );
 
 						if ( ! window.wpActiveEditor ) {
 							window.wpActiveEditor = id;