Post #1822764

About Notification center messages (SF-0011) Great changes to the NotificationCenter API. Now, instead of the abstract Notification, we can define a Sendable type and use it to post and observe messages. The message type must conform to MainActorMessage or AsyncMessage protocol. The first is for time-critical messages. The second is not tied to the main thread and supports AsyncSequence (see examples below). Post continues below. #swift