I am currently developing an iOS widget with SwiftUI and have a strange behaviour of the background-image of my medium-sized widget.

I am setting a background-image depending on the current color mode of the device, which works most of the time. But when the app is in the background for a couple of minutes, the background-image goes black, which makes the text unreadable. Any other UI-elements are still visible. When I resume to my app, the widget refreshes itself and the background-image is visible again.

The background-images are included in my image.assets of my widget-extension, so it should be always accessible for the widget, shouldn’t it?

This widget is available for iOS 14 and above.

This is how I set the background-image:

    struct MediumWidget: View {
           @Environment(\.colorScheme) var colorScheme
    
           var body: some View {
               HStack(alignment: .center, spacing: nil) {
                  // Content (shortend)
               }
               .frame(maxWidth: .infinity, maxHeight: .infinity)
               .edgesIgnoringSafeArea(.all)
               .background(
                    backgroundImage
                    .renderingMode(.original)
                    .resizable()
                    .scaledToFill()
               )
           }
        var backgroundImage: Image {
            if colorScheme == .dark {
                return Image("dark")
            }
            return Image("light")
            
        }
    }

I am clueless of what to do, does someone know what I am doing wrong?

Thank you in advance!

EDIT 1: This problem only occurs with these two background-images. When I use any other background-image, the widget does not go black.