Ticket #31789: 31789.2.diff

src/wp-admin/includes/theme.php

@@ -409 +409 @@
 function wp_prepare_themes_for_js( $themes = null ) {
         $current_theme = get_stylesheet();
 
+        /**
+         * Filter theme data before it is prepared for JavaScript.
+         *
+         * Passing a non-empty array will result in wp_prepare_themes_for_js() returning
+         * early with that value instead.
+         *
+         * @since 4.2.0
+         *
+         * @param array      $prepared_themes An associative array of theme data. Default empty array.
+         * @param null|array $themes          An array of WP_Theme objects to prepare, if any.
+         * @param string     $current_theme   The current theme slug.
+         */
+        $prepared_themes = (array) apply_filters( 'pre_wp_prepare_themes_for_js', array(), $themes, $current_theme );
+
+        if ( ! empty( $prepared_themes ) ) {
+                return $prepared_themes;
+        }
+
         // Make sure the current theme is listed first.
-        $prepared_themes = array( $current_theme => array() );
+        $prepared_themes[ $current_theme ] = array();
 
         if ( null === $themes ) {
                 $themes = wp_get_themes( array( 'allowed' => true ) );