I contacted them and they never replied. This issues appears to be with how Asset Packs are queried by App Store Connect. I just went to approve new versions of Asset Packs for external testing, and all Asset Packs for all my apps are displayed in the list

It appears to be related explicitly to persistent store. Removing the assign call allows the object to be created, modified, saved as expected. Further, I tried to editing objects with the following code let managedObjectContext = managedObjectContext.child(with: .mainQueueConcurrencyType) let object = managedObjectContext.object(with: objectID) as! Object And this crashed with Thread 1: "Object 0x82018e630c8dd320 <x-coredata://E8D86530-2F0D-4680-98AC-D42B1FF23DE4/Object/p33> persistent store is not reachable from this NSManagedObjectContext's coordinator" Again, this isn't an issue for iOS, but it does appear to be an issue for both Mac and VisionOS. It's also not feasible to provide a minimal project that is minimal.

My best guess right now is that something with the managedObjectContext or my CoreDataStack in the environment behaves differently on Mac than it does on iOS and VisionOS. I have 3 stores and the version hash in the metadata is up to date for all of them. So I don't think it's related to the managedObjectModel.

After some more debugging, it appears that the managedObjectModel is nil managedObjectContext.persistentStoreCoordinator?.managedObjectModel

One of these two changes fixe my issue. (1) My CoreDataStack was inside of a package, and the package didn't include .macCatalyst inside of the platforms. Adding it fixed the issue. platforms: [ .macCatalyst(.v26), ], (2) Adding managedObjectContext to the view explicitly inside of a sheet .sheet() { View() .environment(\.managedObjectContext, managedObjectContext) }