CGImageCreate: invalid image alphaInfo: kCGImageAlphaNone. It should be kCGImageAlphaNoneSkipLast

Question

I'm trying to capture a UIVIew as an image, which I can then manipulate. I have code that works in Xcode 11.7/simulator (running iOS 13.7), but throws this error :

CGImageCreate: invalid image alphaInfo: kCGImageAlphaNone. It should be kCGImageAlphaNoneSkipLast

Running on an actual device results in a crash.

Any ideas how I can create this image without the alpha or remove it after the fact?

extension UIView  {
    // render the view within the view's bounds, then capture it as image
  func asImage() -> UIImage {
    let renderer = UIGraphicsImageRenderer(bounds: bounds)
    return renderer.image(actions: { rendererContext in
        layer.render(in: rendererContext.cgContext)
    })
  }
}

It gets called from this code:

@IBAction func reactionListButtonTapped(_ sender: UIButton) {
  guard let reactionVC = storyboard?.instantiateViewController(withIdentifier: "ReactionViewController")
    as? ReactionViewController else {
      
    assertionFailure("No view controller ID ReactionViewController in storyboard")
    return
  }

  // take a snapshot of current view and set it as backingImage
  reactionVC.backingImage = self.view.asImage()

  self.present(reactionVC, animated: false, completion: nil)
}

Thanks for any help.