The issue was that NSLocalNetworkUsageDescription in Info.plist seems to be mandatory on iOS 18.1 now, which it was not in iOS 17. As far as I remember my tests on the released iOS 18.0 and its late betas, it was not mandatory. Since I don't have an iOS 18.0 device anymore and simulators don't check, I cannot reproduce it there. Thanks for the link to TN3179 which is not clear about NSLocalNetworkUsageDescription being mandatory on iOS apps, but gave me the right hint.

The workaround must be applied each time the iOS 15.7 device is rebooted.

The workaround must be applied each time the iOS 15.7 device is rebooted.

Also works on my MacBook Pro M1 Max. Still running Xcode 14 while Xcode 13.4.1 is preparing the iPadOS 15.7 device is not necessary.

Where is the documentation for String(localized:? One month after iOS 15 has been released, the official documentation still declares No overview available and treats it as beta.