This small project crashes when compiled with Swift 6. It does not produce warnings, but crashes when one of the yellow buttons is pressed. The code can be changed to prevent the crash. These changes are marked in the source code with Uncrash. But this just cures the symptoms, not the cause.
Historical: This code was refactored to follow the MVVM architecture. Prior to this the code did not crash.
Who can discover the cause of the crashes?
Update: Claude.ai found the nub of the problem instantly.