public static function add_sender_shutdown() {
    
/**
 * Fires on every request before default loading sync sender code.
 * Return false to not load sync sender code that serializes pending
 * data and sends it to WPCOM for processing.
 *
 * By default this returns true for cron jobs, POST requests, admin requests, or requests
 * by users who can manage_options.
 *
 * @since 4.2.0
 *
 * @param bool should we load sync sender code for this request
 */
    if ( apply_filters(
      'jetpack_sync_sender_should_load',
      self::should_initialize_sender()
    ) ) {
      self::initialize_sender();
      add_action( 'shutdown', array( self::$sender, 'do_sync' ) );
      add_action( 'shutdown', array( self::$sender, 'do_full_sync' ) );
    }
  }