.bottomBar menu button briefly disappears after menu dismissal on iOS 26.1 Seed 2 (23B5059e)

[Also submitted as FB20636175]

In iOS 26.1 Seed 2 (23B5059e), ToolbarItem menus with .bottomBar placement cause the toolbar item to disappear and rebuild after the menu is dismissed, instead of smoothly morphing back. The bottom toolbar can take 1–2 seconds to reappear.

This also seems to coincide with this console error:

Adding 'UIKitToolbar' as a subview of UIHostingController.view is not supported and may result in a broken view hierarchy. Add your view above UIHostingController.view in a common superview or insert it into your SwiftUI content in a UIViewRepresentable instead.

This occurs both on device and in a simulator.

Sample Project

This sample ContentView includes two menu buttons—one in the bottom bar and one in the top bar. Dismissing the bottom bar menu causes a short delay before the button reappears, while the top bar menu behaves normally.

struct ContentView: View {
    var body: some View {
        NavigationStack {
            Text("Tap and dismiss both menu buttons and note the difference.")
            .navigationTitle("BottomBar Menu Issue")
            .navigationSubtitle("Reproduces on iOS 26.1 Seed 2 (23B5059e)")
            .toolbar {
                // Control: top bar trailing menu animates back smoothly
                ToolbarItem(placement: .topBarTrailing) {
                    Menu {
                        Button("Dismiss", role: .cancel) { }
                        Button("Do Nothing") { }
                    } label: {
                        Label("More", systemImage: "ellipsis.circle")
                            .font(.title3)
                    }
                }

                // Repro: delay before menu button reappears after menu dismissal
                ToolbarItem(placement: .bottomBar) {
                    Menu {
                        Button("Dismiss", role: .cancel) { }
                        Button("Do Nothing") { }
                    } label: {
                        Label("Actions", systemImage: "ellipsis.circle")
                            .font(.title2)
                    }
                }
            }
        }
    }
}

Passwords App

This can also be seen in iOS 26.1 Seed 2 (23B5059e)'s Passwords app ("All" or "Passcodes" views):