How to auto-resize a SwiftUI sheet on macOS to fit its content?

Code Block swift
struct ContentView: View {
    @State var showSheet = false
    var body: some View {
        VStack {
            Text("Hello, world!").padding()
            Button("Show sheet") {
                showSheet = true
            }
        }
        .sheet(isPresented: $showSheet) {
            SheetView()
        }
    }
}
struct SheetView: View {
    @State var greenBiggerBox = false
    var body: some View {
        VStack {
            Toggle("Show bigger box", isOn: $greenBiggerBox)
            if greenBiggerBox {
                Rectangle().frame(width: 640, height: 480).foregroundColor(.green)
            } else {
                Rectangle().frame(width: 320, height: 240).foregroundColor(.red)
            }
        }.padding()
    }
}