Unowned capture of actor doesn't report concurrency violation

Using Swift
,
1

Here is a code sample that I don't quite know how to interpret:

actor Test {
    var x: Int = 0

    func compiles() -> some Publisher {
        return Just(1)
            .handleEvents(receiveCompletion: { _ in
                // Compiles ok
                self.x += 1
            })
    }

    func compiles2() -> some Publisher {
        return Just(1)
            .handleEvents(receiveCompletion: { [unowned self] _ in
                // Compiles ok
                self.x += 1
            })
    }

    func doesnCompile() -> some Publisher {
        return Just(1)
            .handleEvents(receiveCompletion: { [weak self] _ in
                // Actor-isolated property 'x' can not be mutated from a non-isolated context
                self?.x += 1
            })
    }

    func doesnCompile2() -> some Publisher {
        return Just(1)
            .handleEvents(receiveCompletion: { _ in
                unowned var actor = self
                // Actor-isolated property 'x' can not be mutated from a non-isolated context
                actor.x += 1
            })
    }
}

The behaviour is the same in Minimal and Complete concurrency checking

I would have expected all of these examples to not compile. Is there some explanation for this behaviour?

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