Post #4280272

https://github.com/tc39/proposal-temporal/issues/1751 I am so angry at this. The working group correctly identified that if your input string to PlainDateTime has Z then it’s a UTC timestamp and probably a bug in hiding (so it blows up). But it didn’t acknowledge that _any_ offset, not just UTC, is the same problem! So it should blow up for any offset, not just UTC! Type theory mindedness would have saved us from this colossal mistake