Customize sidebar button image in split-view

Question

I have a SwiftUI app. On iPad, the sidebar icon (top-left) appears when split-view is active.

I can't hide it using .navigationBarBackButtonHidden(true) to make my own custom one.

How can I fix this?

Code:

struct ContentView: View {
    
    var body: some View {
        NavigationView {
            Text("Sidebar")
            
            Text("Main content")
        }
    }
}