focusedSceneValue doesn't work with Window

My observations:

• Passing a FocusState.Binding using focusedSceneValue seems to work only when the app uses a WindowGroup.

• When the app uses a Window (single window) passing the FocusState.Binding in focusedSceneValue doesn't seem to work.

• When app uses Window passing FocusState.Binding using focusedValue and receiving it in @FocusedValue seems to work.

Question:

Is this expected behaviour? (should focusedSceneValue only work for WindowGroup and not for Window?)