I'm using Xcode 12.5.1 and creating a new iOS Game project with SpriteKit:

1. File
2. New project
3. iOS, Game
4. Language: Swift, Game Technology: SpriteKit

Running it without any modification on the iOS simulator (e.g. "iPhone 12 mini") leads to this screen:

[![Screenshot of default SpriteKit app on iOS simulator (running)](https://i.stack.imgur.com/gDoLn.png)](https://i.stack.imgur.com/gDoLn.png)

This looks fine, it has black borders around the scene. However, when I swipe from the bottom to go into the Task Switcher, the black border suddenly turns into a grey/white border:

[![Screenshot of default SpriteKit app on iOS simulator (in task switcher)](https://i.stack.imgur.com/T2G92.png)](https://i.stack.imgur.com/T2G92.png)

I also tried changing the "Background" property of the "View" in `Main.storyboard` to black like this, which has no effect on the task switcher appearance:

[![Screenshot of Xcode with the background of the "View" in Main.storyboard set to "Black"](https://i.stack.imgur.com/QJoBV.png)](https://i.stack.imgur.com/QJoBV.png)

This should be easy to reproduce by just creating the default SpriteKit example app, running it on a real phone or a simulator and going into task switcher view.

I want the background of the app in the Task Switcher to be black in the task switcher view, just like when the app is running. Note that the app I'm creating has a fixed aspect ratio for the `SKSpriteNode` I'm using, so the solution shouldn't involve setting a different size to the Scene. Basically it should work for any aspect ratio and letterbox my `SKSpriteNode` in the view with black letterboxing in both app view and app switcher view.