title: why useObserver hook won't rerender twice, comparing to observer hoc?
body: <p>I'm reading the docs of mobx-react-lite and confusing with the difference between observer hoc and useObserver hook. According to the docs, observer hoc will trigger re-render twice while useObserver won't:</p>
  
  <blockquote>
    <p>One good thing about this is that if any hook changes an observable for some reason then the component won't rerender twice unnecessarily. (example pending)</p>
  </blockquote>
  
  <p>I'm not so familiar with mobx-react-lite, but interested in what causes that differences.
  Here is the docs: <a href="https://mobx-react.js.org/observer-hook" rel="nofollow noreferrer">https://mobx-react.js.org/observer-hook</a></p>