iPhone XS Max/XR screen size when building via Xcode 9

A few days ago I noticed that my app's UI was being scaled incorrectly on an iPhone XS Max and XR. After reading some tutorials and articles on the Internet, I found out that this was because of the launch images in my project. I replaced the launch images with a launch storyboard and all seemed to work fine... but only when I build my app via Xcode 10. This is not the case for Xcode 9 (I use this version of Xcode on my CI). I understand that the app is unaware of the existence of the iPhone XS Max/XR screen size, so the UI is zoomed to fill the larger screen. My problem is that I create another UIWindow object (taking the screen dimensions from UIScreen.main.bounds) and, later on, present an UIImagePickerController inside it's root view controller. The UIImagePickerController's view is displayed incorrectly (the top edge of it's view goes beyond the safe area) on iPhones XS Max and XR when building via Xcode 9.