Falcon_Handler::supports_message_ids PHP Метод

    public static function supports_message_ids();

 /**
  * Send a notification to subscribers
  */
 public function notify_on_reply($id = 0, $comment = null)
 {
     if (empty($this->handler) || !Falcon::is_enabled_for_site()) {
         return false;
     }
     if (wp_get_comment_status($comment) !== 'approved') {
         return false;
     }
     // Is the post published?
     $post = get_post($comment->comment_post_ID);
     if (get_post_status($post) !== 'publish') {
         return false;
     }
     // Grab the users we should notify
     $users = $this->get_comment_subscribers($comment);
     if (empty($users)) {
         return false;
     }
     $message = new Falcon_Message();
     // Poster name
     $message->set_author(apply_filters('falcon.connector.wordpress.comment_author', $comment->comment_author));
     // Don't send notifications to the person who made the post
     $send_to_author = Falcon::get_option('bbsub_send_to_author', false);
     if (!$send_to_author && !empty($comment->user_id)) {
         $author = (int) $comment->user_id;
         $users = array_filter($users, function ($user) use($author) {
             return $user->ID !== $author;
         });
     }
     // Sanitize the HTML into text
     $message->set_text($this->get_comment_content_as_text($comment));
     $message->set_html($this->get_comment_content_as_html($comment));
     $subject = apply_filters('bbsub_email_subject', 'Re: [' . get_option('blogname') . '] ' . html_entity_decode(get_the_title($post), ENT_QUOTES), $id, $post->ID);
     $message->set_subject($subject);
     $message->set_reply_address_handler(function (WP_User $user, Falcon_Message $message) use($comment) {
         return Falcon::get_reply_address('comment_' . $comment->comment_ID, $user);
     });
     $options = array();
     if ($this->handler->supports_message_ids()) {
         $options['references'] = $this->get_references_for_comment($comment);
         $options['message-id'] = $this->get_message_id_for_comment($comment);
         if (!empty($comment->comment_parent)) {
             $parent = get_comment($comment->comment_parent);
             $options['in-reply-to'] = $this->get_message_id_for_comment($parent);
         } else {
             $options['in-reply-to'] = $this->get_message_id_for_post($post);
         }
     } else {
         $message_ids = get_post_meta($id, self::MESSAGE_ID_KEY, $responses);
         $options['in-reply-to'] = $message_ids;
     }
     $message->set_options($options);
     $this->handler->send_mail($users, $message);
     return true;
 }