iOS26 beta ToolbarItem with placement to principal width is not fill to screen

I’m trying to add a TextField to the toolbar using .principal placement, and I want it to either fill the screen width or expand based on the surrounding content. However, it’s not resizing as expected — the TextField only resizes correctly when I provide a hardcoded width value. This behavior was working fine in previous versions of Xcode, but seems to be broken in Xcode 26. Not sure if this is an intentional change or a bug. i am using iOS26 beta and Xcode 26 beta

struct ContentView: View {
    var body: some View {
        VStack {
            Image(systemName: "globe")
                .imageScale(.large)
                .foregroundStyle(.tint)
            Text("Hello, world!")
        }
        .padding()
        .toolbar {
            ToolbarItem(placement: .principal) {
                HStack {
                    TextField("Search", text: .constant(""))
                        .textFieldStyle(.roundedBorder)
                        .frame(maxWidth: .infinity)
//                        .frame(width: 300)
                    Button("cancel") {
                        
                    }
                }
                .frame(maxWidth: .infinity)
            }
        }
    }
}

#Preview {
    NavigationView {
        ContentView()
    }
}
iOS26 beta ToolbarItem with placement to principal width is not fill to screen
 
 
Q