`onBecomeUnobserved` not triggered immediately on `useObserver` component unmount

Intended outcome: onBecomeUnobserved triggered when the component wrapped with observer is unmounted

Actual outcome: onBecomeUnobserved never triggered or triggered randomly

How to reproduce the issue:

https://codesandbox.io/s/practical-ioana-6sthfs?file=/src/App.tsx

Versions

seems like it's reproduced on any version