App Becomes Unresponsive for iOS/iPadOS 18 Regular Size Class Interactions When Selecting One Particular View in Sidebar

@aandyzoom01 The code snippets in your Feedback report is incomplete, could you provide a focused sample project that reproduces the issue? I can investigate the issue more effectively in a focused sample project.

My production App Store app can be run on iOS/iPadOS 18 Beta. Here is the App Store link: Starship SE Corps This plus the provided code excerpts should be sufficient to view the issue in context until I have a chance to try a focused Xcode test project with the risk that a test project doesn’t show the issue like my actual production app does.

I've narrowed down the issue further as follows: Reference the FB13917278_Sample_App Xcode project I placed in the feedback running on iPadOS 18.0 Simulator

1. If I change the SidebarView to make the FunctionView() launch as the detail view, the FunctionView displays correctly and works correctly when the user interacts with the List and children.
2. However, if I navigate to the StartingView (works ok), then navigate back to the FunctionView, the problem is seen and the FunctionView does not appear.

Therefore, the problem appears to be with the NavigationSplitView and NavigationStack going from another view in the sidebar list to the FunctionView.

When doing step 1 and launching the app I get the following console log messages: NSBundle file:///Library/Developer/CoreSimulator/Volumes/iOS_22A5282m/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS%2018.0.simruntime/Contents/Resources/RuntimeRoot/System/Library/PrivateFrameworks/MetalTools.framework/ principal class is nil because all fallbacks have failed

If I don't interact with the simulator within a few seconds, I get these additional messages:

[C:4-1] Error received: Invalidated by remote connection. Found no UIEvent for backing event of type: 3; contextId: 0xACBED546

If I interact with the FunctionView list, I get this additional message: Failed to create 0x88 image slot (alpha=1 wide=1) (client=0xd02d59c7) [0x5 (os/kern) failure]

If I change the SidebarView to back to make the StartingView() launch as the detail view, I get the following console messages upon launch into Portrait orientation: Failed to send CA Event for app launch measurements for ca_event_type: 0 event_name: com.apple.app_launch_measurement.FirstFramePresentationMetric Failed to send CA Event for app launch measurements for ca_event_type: 1 event_name: com.apple.app_launch_measurement.ExtendedLaunchMetrics

If I then switch to Landscape orientation, I get the following additional console messages: [C:4-1] Error received: Invalidated by remote connection. Found no UIEvent for backing event of type: 3; contextId: 0xD9737857

If I launch into Portrait orientation then immediately switch to Landscape orientation, I get no console messages, but trying to navigate to the FunctionView displays nothing and the app becomes unresponsive.