Ticket #23902: nav-menu-template.php.patch

src/wp-includes/nav-menu-template.php

@@ -95 +95 @@
                  * @param object $item    The current menu item.
                  * @param array  $args    An array of wp_nav_menu() arguments.
                  */
-                $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );
+                $classes = apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args );
+                $item->classes = $classes;
+
+                $class_names = join( ' ', $classes );
                 $class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';
 
                 /**