I'm doing a basic modal presentation from one view controller to another, with my modal presentation style set to .fullScreen and my modal transition style set to .partialCurl. When I call dismiss(animated:) on the second view controller, it starts the .partialCurl transition, but then it freezes halfway, at the point when the second view controller is deinitialized. It happens both with the Simulator and with my iPad device. It does not happen with any of the other modal transition styles, just .partialCurl. Any ideas what I might be doing wrong? ... Relevant modal presentation code in the first view controller: let vc2 = ViewController2() vc2.modalPresentationStyle = .fullScreen vc2.modalTransitionStyle = .partialCurl   present(vc2, animated: true, completion: nil) Relevant modal presentation code in the second view controller: dismiss(animated: true)