add_action('wishlist_single_meta', 'wishlist_single_meta_20201908', 0); function wishlist_single_meta_20201908($atts){ $wishlist_id = isset( $atts['id'] ) ? $atts['id'] : 0; //echo '<pre>'.var_export($wishlist_id, true).'</pre>'; ?> <span>Custom HTML here</span> <?php }