Selecting wrong image from Light/Dark choices

I have an icon. I made a white version so I could support dark mode. But when I put the preview (SwiftUI) to dark mode, I get what is in Any, not what is in Light or Dark. So I have a white outlined version in Dark and a black one in Light and then I cannot leave Any empty. Whatever I put in there is what I will get. I am thinking maybe I have to do something in the app (I do with Material on Android), but that does not seem to be the case as the demos did not show any code changes. Maybe it's a bug?