what's wrong with `ToolbarItemGroup(placement: .keyboard)` inside `TavView`?

Why is there inconstancy of appearing the keyboard tool bar Item with tab view? Try to go to second tab and focus the field. Sometimes it does not appear (in my more complex project it does not appear >90% times).

import SwiftUI

struct MainTabView: View {
    var body: some View {
        TabView {
            FirstTabView()
                .tabItem { Label("Tab 1", systemImage: "house") }
            SecondTabView()
                .tabItem { Label("Tab 2", systemImage: "star") }
        }
    }
}

struct FirstTabView: View {
    @State private var text = ""

    var body: some View {
        NavigationStack {
            VStack {
                TextField("Enter something 1", text: $text)
                    .textFieldStyle(RoundedBorderTextFieldStyle())
                    .padding()
            }
            .toolbar {
                ToolbarItemGroup(placement: .keyboard) {
                    Button("Done") { UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil) }
                }
            }
        }
    }
}

struct SecondTabView: View {
    @State private var text = ""

    var body: some View {
        NavigationStack {
            VStack {
                TextField("Enter something 2", text: $text)
                    .textFieldStyle(RoundedBorderTextFieldStyle())
                    .padding()
            }
            .toolbar {
                ToolbarItemGroup(placement: .keyboard) {
                    Button("Done") { UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil) }
                }
            }
        }
    }
}

#Preview {
    MainTabView()
}