title: Visual Effect window and a label
body: <p>I can make all the window with a visual effect. But I cannot see the label when I apply the effect:</p>
  
  <pre><code>@IBOutlet weak var label1: NSTextField!
  
  override func viewWillAppear() {
      super.viewWillAppear()
  
      let visualEffect = NSVisualEffectView()
      visualEffect.blendingMode = NSVisualEffectView.BlendingMode.behindWindow
      visualEffect.material = NSVisualEffectView.Material.dark
      view.window?.contentView = visualEffect
  
  }
  </code></pre>
  
  <p>Here there is a very good solution:
  <a href="https://stackoverflow.com/questions/58940252/how-to-make-a-window-with-rounded-corners">How to make a window with rounded corners</a></p>
  
  <p>I tried to change my last line with that, but then the visual effect disappears:</p>
  
  <pre><code>view.addSubview(visualEffect, positioned: .below, relativeTo: label1)
  </code></pre>
  
  <p>How to have a visual effect in the window and be able to have also a label?</p>