Thanks for the reply. I'm not sure that speaks to my concern. I am talking about the way you can switch the window in which a cursor appears simply by looking at it; and not just your own app windows, but all app windows. Whereas with MacOS iPadOS you have to manually move the cursor to the new window and click on it to get focus, with visionOS, you simply turn your attention and move the cursor, not even needing to click. Ideally, I would like to be able to reject that cursor focus.

I suspect the key step here is the unpairing. I followed these steps, and it did not work for me until I restarted Xcode.

Interestingly, if I override traitCollectionDidChange in my child view controller, add a breakpoint there, and print the traitCollection of its view in the debugger, it shows the inherited traitCollection correctly and then proceeds to lay out the view properly. But unless I do that print, the value stays the old one for the child view controller's view.

Thanks for the great feedback. I have switched to nesting my UIView in a UIViewController which I then add as a child view controller to another controller. I can successfully override the child view controller's trait collection, but the child view controller's view trait collection property does not seem to inherit the change and so when I call layoutIfNeeded(), the layout does not reflect the new trait collection. Can you suggest how to ensure the child view controller's view inherits the setOverrideTraitCollection change?