title: Child doesnt respect parent height
body: <p>Im trying to make a vertical scroll on my <code>.left</code>  class.</p>
  <p>When i try to instert <code>overflow-y: scroll</code>, nothing happens.
  I tried to set <code>max-height</code> on parent container, but its exceeds the div limits
  I tried to set also <code>overflow-y: scroll</code> on <code>.left</code> divider.</p>
  <p>Here is a reproduction.</p>
  <blockquote>
  <p>Stackblitz:
  <a href="https://stackblitz.com/edit/web-platform-49iyin?file=index.html" rel="nofollow noreferrer">https://stackblitz.com/edit/web-platform-49iyin?file=index.html</a></p>
  </blockquote>