NavigationSplitView does not work inside NavigationStack

When using a NavigationSplitView within a NavigationStack, the NavigationSplitView does not work as expected on iOS 18 (it worked previously). Items do not show their associated detail views when selected.

See the following minimum reproducible example:

import SwiftUI

struct ContentView: View {
	@State var selectedItem: String? = nil
	@State var navigationState: NavigationState? = nil
	
	var body: some View {
		NavigationStack {
			List(selection: self.$selectedItem) {
				NavigationLink("Item 1", value: "item")
			}
			.navigationDestination(item: self.$selectedItem) { value in
				ChildView()
			}
		}
	}
}

enum NavigationState: Hashable {
	case general
	case secondary
}

struct ChildView: View {
	@State var navigationState: NavigationState? = nil
	
	var body: some View {
		NavigationSplitView {
			List(selection: self.$navigationState) {
				NavigationLink(value: NavigationState.general) {
					Text("Basic info")
				}
				NavigationLink(value: NavigationState.secondary) {
					Text("Secondary info")
				}
			}
		} detail: {
			if self.navigationState == nil {
				Text("Nothing")
			} else {
				Text("Details")
			}
		}
	}
}