This whole feature works perfectly on all other versions of iOS below 13.0.
My general advice in situations like this, where you have existing code that’s failing on a pre-release system, is to file a bug. It’s possible that you’re doing something wrong that just happened to work on previous systems, but it’s just as likely that this is a bug in the system itself.
Please post your bug number, just for the record.
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Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware
let myEmail = "eskimo" + "1" + "@apple.com"
The issue seems to have been fixed in the latest beta 13.0(17a5556d).