Ticket #31982: 31982.6.diff

src/wp-includes/class-wp-customize-setting.php

@@ -1103 +1103 @@
                         $i = 1;
 
                         foreach ( $items as $k => $item ) {
-                                $items[ $k ]->$args['output_key'] = $i++;
+                                $items[ $k ]->{$args['output_key']} = $i++;
                         }
                 }
 

src/wp-includes/nav-menu.php

@@ -638 +638 @@
                 usort($items, '_sort_nav_menu_items');
                 $i = 1;
                 foreach( $items as $k => $item ) {
-                        $items[$k]->$args['output_key'] = $i++;
+                        $items[$k]->{$args['output_key']} = $i++;
                 }
         }