UITextField doesn't present keyboard view on UISearchContainerViewController

I have a view controller with a text field on it. In general, it works fine. But when this view controller is presented from a search results view controller the text field doesn't react on taps.

The results controller is wrapped in UISearchController and at the same time, UISearchController is placed to UISearchContainerViewController.

let resultsController = SearchResultsViewController()
let searchController = UISearchController(searchResultsController: resultsController)
let container = UISearchContainerViewController(
    searchController: searchController)
container.view.backgroundColor = .black
present(container, animated: true)

I pushed a small example on GitHub.

There is a workaround to make the text field work: add UISearchContainerViewController as a child controller on some dummy view controller and present it. But such an approach involves weird memory leaks which I'd like to avoid.