swift - How to access an actor-isolated property?

Question

I try to check the actor's behavior. This is a new feature provided by Swift5.5.

I've created a playground with an example code from the official documentation swift.org:

    import Foundation
    
    actor TemperatureLogger {
        let label: String
        var measurements: [Int]
        private(set) var max: Int

        init(label: String, measurement: Int) {
            self.label = label
            self.measurements = [measurement]
            self.max = measurement
        }
    }

    let logger = TemperatureLogger(label: "Outdoors", measurement: 25)
    print(await logger.max)
    // Prints "25"

But my compiler fails on this example:

Swift Compiler Error:

'await' in a function that does not support concurrency

Actor-isolated property 'max' can only be referenced from inside the actor

So how to access an actor-isolated property?

Maybe it's a bug in the compiler or in the example code?

Xcode Version 13.0 beta (13A5154h) Swift Version 5.5