SwiftApp.swift

import SwiftUI

@main
struct SwiftApp: App {
    
    @State var someState = false

    var body: some Scene {
        WindowGroup {
            Rectangle()
                .foregroundColor(someState ? .blue : .secondary)
                .frame(width: 200, height: 200)
                .padding(50)
                .onTapGesture {
                    someState = !someState
                }
                .navigationTitle("SwiftUI Title")
                .onAppear {
                    DispatchQueue.main.async {
                        NSApp.windows.first?.title = "Overridden Title"
                    }
                }
        }
    }
}