Size Class Issue

This is a demo project showcasing what looks like an issue with size classes on visionOS.

Here's my expectations:

The horizontalSizeClass environment variable should reflect the size of the current window and allow me to update my interface accordingly. When resizing the window from a large canva, to make it smaller, it should be updated and transition from .regular to .compact at some point.

In this sample project, I have a collection of colorful rounded rectangles. Depending on the horizontal size class, I want to change the layout from a two flexible columns LazyVGrid to a List. You can find this View in ContentView.swift.

What is currently happening:

The horizontalSizeClass seems to be locked to the .regular value. Resizing the window to its smallest possible size never triggers any change of this value.

ContentView always feature a grid and never transition to a List.

Reproduction steps

• Build this sample project for Apple Vision Pro Simulator.
• Resize the window and observe the behavior of the ContentView. Notice that it's always a Grid and that it never becomes a List.
• Notice the value in the center of the window. This is an overlayed geometry reader printing the view width. This geometry reader updates correctly. Which I find interesting because it narrows down the problem to size classes support.
• Optionally set a breakpoint to ContentView.swift line 23 and ContentView.swift line 30. You'll find that only the breakpoint for the Grid (23) is called. We never reach the breakpoint for the List (30).

Notes

This issue was diagnosed using visionOS SDK Beta 2. I was able to reproduce this issue on an actual Apple Vision Pro during a lab. This issue is also reproducible in the visionOS Simulator in Xcode Beta 6.