[pjmlp]

Not in Java, .NET and C++ case, as it is mapped to tasks, managed by threads, and you can even write your own scheduler if so inclined.

[Someone]

Also (AFAIK) not in JavaScript. An essential property of cooperative multitasking is that you can say “if you feel like it, pause me and run some other code for a while now” to the OS.

Async only allows you to say “run foo now until it has data” to the JavaScript runtime.

IMO, async/await in JavaScript are more like one shot coroutines, not cooperative multitasking.

Having said that, the JavaScript event loop is doing cooperative multitasking (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Even...)