Are extensions of @MainActor classes on the main actor?

Question

If a class is on @MainActor:

@MainActor class MyClass : NSObject
{
}

does this put all its extensions on @MainActor as well?

extension MyClass
{
}

Answer 1

Yes. As SE-0316 - Global actors says:

A type declared with a global actor attribute propagates the attribute to all methods, properties, subscripts, and extensions of the type by default.