refactoredPushNavigation.swift

class AppDelegate: UIApplicationDelegate {
    func application(_ app: UIApplication,
                     didReceiveRemoteNotification userInfo: [AnyHashable: Any],
                     fetchCompletionHandler _: @escaping (UIBackgroundFetchResult) -> Void) {
        rootNavigationController.navigate(with: userInfo)
    }
}

class MyNavigationController: UINavigationController {
    func navigate(with userInfo: [String: AnyObject?] {
        let destination = userInfo["destination"]
        if destination == ThirdViewController.className {
        viewControllers = [FirstViewController.storyboardInstance, SecondViewController.storyboardInstance, ThirdViewController.storyboardInstance]
        }
        else if /// 등등...
    }
}