Ticket #33218: 33218.patch

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

@@ -230 +230 @@
         'echo' => true, 'fallback_cb' => 'wp_page_menu', 'before' => '', 'after' => '', 'link_before' => '', 'link_after' => '', 'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
         'depth' => 0, 'walker' => '', 'theme_location' => '' );
 
-        // Prevent a fallback_cb in Customizer Preview to assist with has_nav_menu() and partial refresh.
-        if ( is_customize_preview() ) {
-                $defaults['fallback_cb'] = '';
-        }
-
         $args = wp_parse_args( $args, $defaults );
         /**
          * Filter the arguments used to display a navigation menu.