I'm having the same issue. I have a project targeting iOS 12 and previews worked great with Xcode 13 but are completely broken with Xcode 14+. It seems to be related to how the compiler handles primitives. I created a barebones project targeting iOS 12 and the previews work fine if there are no primitive values in the file, but as soon as there is a primitive being used it breaks, but using a collection of primitives works fine. Strangely if I move the preview code to a separate file it works fine, so this definitely seems like an Xcode 14 bug or the compiler has been tightened up and we can't do the #if DEBUG @available(iOS 13, *) workaround anymore. import UIKit class ViewController: UIViewController {     override func viewDidLoad() {         super.viewDidLoad()         // UIView works         let view = UIView()         // An array of strings works         let strArray = [String]()         // Using a string breaks         let str = "hello world!"         // Using a CGFloat breaks         let num: CGFloat = 1337         // Using a Bool breaks         let bool = false     } } #if DEBUG import SwiftUI @available(iOS 13, *) struct Test_Previews: PreviewProvider {     static var previews: some View {         Group {             Color.orange.frame(height: 100)         }     } } #endif

I just saw this happening too, then I realized that the code wasn't being called. Meaning once the app compiled and the compiler realized it was not possible for the breakpoint to ever hit it would turn to the dotted outline. At least that was the case for me.

Changed my comment to an answer