Thanks for all the effort you've put in to deal with this problem. Have you any idea why I can't reproduce it on my MacOS 12.4 machine? I may be writing to a log file outside the sandbox but I don't think it would cause the observed crash. I've tried running the app in a fresh account (using the distribute to development team archive option) on the dev Mac but it doesn't crash. A non-reproducible problem I'm having is that sometimes the app menu bar is unresponsive - sub-menus are only visible when the touchpad is pressed. The app then has to be stopped from Xcode or killed using Activity Monitor. Sometimes windows shown do not respond to the close button. Could these be connected with the crash which the app reviewer encountered?

Full crash log attached: Crash log (.ips file)

Rebuilt the toolbar in Xcode 13.4 but flexible space toolbar item does not have any width, so replaced with 3 regular spaces to give apperance as shown below. When run on Catalina the toolbar appears as in the first image.

Checking Hide Title Text in the panel attributes results in the expected display in Xcode 13.4 in design mode but when run, the application spaces the toolbar items so much that the right-hand ones disappear and are shown in a disabled menu

XCode 12.3 issue on Catalina appeared after deleting DerivedData Folder for project. Closing and re-opening XCode project, and cleaning build folder eventually worked.

Same problem with iOS 12.5.5 on iPhone 6

After adding a subscription from a new Sandbox account (set in App Store Connect) the iPhone shows the email address of the new account as Apple ID: newemail, but clicking on only shows Cancel and Sign In options, not Manage.

This problem often recurs, even with a new account and using the bash shell. Closing and re-opening Xcode seems to fix it.

I think the answer is the that System icons/images are SFSymbols, which are only supported for iOS 13 or later. Doco recommends exporting as SVG and bundling with app to use in older versions using SFSymbols app

Some additional data - Xcode debug windows shows CaptionEdit[1137:31772] Could not load the "gearshape.fill" image referenced from a nib in the bundle with identifier "com.AlekaConsulting.CaptionEdit" and "CaptionEdit[1137:31772] libMobileGestalt MobileGestalt.c:890: MGIsDeviceOneOfType is not supported on this platform." when images not shown

Even though the options are greyed out, clicking on the download (down arrow) icon shows a screen "Xcode is trying to install Apple-provided software" and prompts of credentials to allow this. The simulator download then proceeds and the greyed out down arrow is eventually replaced by a blue tick, and simulators for devices using the downlooed iOS appear in options.

I cannot install from XCode Preferences as all the simulators listed are greyed out. Will command line installation be any different?

This problem appeared during development in a new account which was created after the problem appeared in the original development account without any changes to the shell, which is bash (both default and running as shown by ps -o comm= $$ and echo $SHELL)

I'm using XCode 12.3 so the highest iOS version is 14.3 rather than 15.4 but the procedure above worked OK - thanks

Restarting XCode worked