Help/About: Run image comparison script after all assets have loaded.

If the callback is called before the images are loaded, the comparison doesn't work. `wp.domReady` uses `DOMContentLoaded`, which does not guarantee that the images are loaded. This switches to use the `load` event, which waits for all resources to load.

Props vladytimy, joyously, sergeybiryukov.
Merges [50535] to the 5.7 branch.
Fixes #52758.


Built from https://develop.svn.wordpress.org/branches/5.7@50536


git-svn-id: http://core.svn.wordpress.org/branches/5.7@50149 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/about.php

@@ -239,7 +239,7 @@ require_once ABSPATH . 'wp-admin/admin-header.php';
 <?php require_once ABSPATH . 'wp-admin/admin-footer.php'; ?>
 
 <script>
-	wp.domReady( function() {
+	window.addEventListener( 'load', function() {
 		var createElement = wp.element.createElement;
 		var Fragment = wp.element.Fragment;
 		var render = wp.element.render;

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.7.1-alpha-50526';
+$wp_version = '5.7.1-alpha-50536';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.