public static function GetStarted () {
		if (static::$started === NULL) {
			$req = self::$req ?: self::$req = & \MvcCore\Application::GetInstance()->GetRequest();
			if (!$req->IsCli()) {
				$alreadyStarted = session_status() === PHP_SESSION_ACTIVE && session_id() !== '';
				if ($alreadyStarted) {
					// if already started but `static::$started` property is `NULL`:
					static::$sessionStartTime = time();
					static::$sessionMaxTime = static::$sessionStartTime;
					static::setUpMeta();
					static::setUpData();
				}
				static::$started = $alreadyStarted;
			}
		}
		return static::$started;
	}