Flarum\Event\ConfigureModelDates::isModel PHP Method

    public function isModel($model)
    {
        return $this->model instanceof $model;
    }

 /**
  * @param ConfigureModelDates $event
  */
 public function configureModelDates(ConfigureModelDates $event)
 {
     if ($event->isModel(User::class)) {
         $event->dates[] = 'flags_read_time';
     }
 }