PopoversBackground.swift

struct ContentView: View {
    @State var present = false
    
    var body: some View {
        Button("Present popover!") {
            present = true
        }
        .frameTag("Button")
        .popover(present: $present) {
            Text("Hi, I'm a popover.")
                .padding()
                .foregroundColor(.white)
                .background(.blue)
                .cornerRadius(16)

        } background: {
            PopoverReader { context in
                Templates.CurveConnector(
                    start: context.frame.point(at: .top),
                    end: context.window.frameTagged("Button").point(at: .bottom)
                )
                .stroke(Color.blue, lineWidth: 4)
            }
        }
    }
}