localizedDescription The operation couldn’t be completed

Hi everyone,
I declare errorDescription asynchronous property.
That's OK when I call await errorDescription
But got "The operation couldn’t be completed" when accessing localizedDescription
As nserror bridging
The runtime would need to register a user info value provider for each error type the first time it is bridged into NSError , supplying the domain and the following user info value provider function

That’s a bug?

enum MyError: LocalizedError {
    case unknownError
    var errorDescription: String {
        get async {
            switch self {
            case .unknownError:
                try! await Task.sleep(nanoseconds: 1_000_000)
                return "Custom unknown error"

Task {
    print(await MyError.unknownError.errorDescription) //Custom unknown error

print(MyError.unknownError.localizedDescription) //The operation couldn’t be completed.

A protocol conformance cannot add async or throws, but it can remove them.

It can also remove ? from a failable initializer, but not from a method/property/subscript.

Your errorDescription doesn't match the protocol requirement, so I think your conformance is using a default implementation (which returns nil).