Xcode 11 navigation bar is not translucent

Question

Just switched to Xcode 11 beta 4. Tried doing some work with Navigation Controller but I can't seem to get my navigation bar to be translucent. The code works fine on Xcode 10 though. Any idea how to resolve this?

let redVC = UIViewController()
redVC.view.backgroundColor = .red
redVC.navigationItem.title = "First"
let redNavController = UINavigationController(rootViewController: redVC)
redNavController.tabBarItem.title = "First"
redNavController.navigationBar.prefersLargeTitles = true