I added the button style .glass but this does not change anything. Button styles .bordered, .plain.or .glassProminent produce a sharp selected button. Button styles .glass or .automatic to a blurred selection. struct ContentView: View { @State private var items = [ "Item 1", "Item 2", "Item 3", "Item 4"] var body: some View { ZStack { Image(systemName: "globe") .resizable() List(items, id: \.self) { item in Button(action: {}, label: { Text(item) }) .buttonStyle(.glass) } .padding() .glassEffect(in: Rectangle()) } } }

I got this link from a Reddit user: https://twitter.com/rokhinip/status/1403375411732439044 So, now it is clear that the code should work as expected but it doesn't because I am still on Big Sur.

By the way, if I put longCalculation on a concurrent GCD queue than it works as expected. But I wonder if it is really meant to be like this.