Flarum\Core\Notification\NotificationServiceProvider::registerNotificationTypes PHP Method

    public function registerNotificationTypes()
    {
        $blueprints = ['Flarum\\Core\\Notification\\DiscussionRenamedBlueprint' => ['alert']];
        $this->app->make('events')->fire(new ConfigureNotificationTypes($blueprints));
        foreach ($blueprints as $blueprint => $enabled) {
            Notification::setSubjectModel($type = $blueprint::getType(), $blueprint::getSubjectModel());
            User::addPreference(User::getNotificationPreferenceKey($type, 'alert'), 'boolval', in_array('alert', $enabled));
            if ((new ReflectionClass($blueprint))->implementsInterface('Flarum\\Core\\Notification\\MailableInterface')) {
                User::addPreference(User::getNotificationPreferenceKey($type, 'email'), 'boolval', in_array('email', $enabled));
            }
        }
    }