title: `overflow:auto` not working in Chrome with dynamic height
body: <p>I'm trying to make the content of a <code>details</code> element scrollable, only using CSS (i.e. no JS). The height of this <code>details</code> is dynamic, based on the viewport.</p>
  <p>On Firefox, I obtain the expected result. But on Chrome, the <code>overflow:auto</code> has no impact in this case:</p>
  <p>Firefox (expected result):</p>
  <p><a href="https://i.stack.imgur.com/qZnmY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qZnmY.png" alt="enter image description here" /></a></p>
  <p>Chrome (wrong behavior):</p>
  <p><a href="https://i.stack.imgur.com/2haPR.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2haPR.png" alt="enter image description here" /></a></p>
  <p>When setting a fixed height, the content is scrollable on Chrome, but I want it to be dynamic.</p>
  <p>Here's the simplified code:</p>
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="false" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-css lang-css prettyprint-override"><code>* {
    box-sizing: border-box;
  }
  
  :root {
    --summary-height: 32px;
    --text-color: antiquewhite;
  }
  
  details {
    width: 200px;
    border: 1px solid dimgray;
  }
  
  details[open] {
    height: 64vh;
    flex: 1 1 0;
  }
  
  summary {
    background-color: dimgray;
    color: var(--text-color);
    text-shadow: 0 0 3px #1a1a1a;
    height: var(--summary-height);
    line-height: var(--summary-height);
  }
  
  ul {
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
    list-style: none;
    margin: 0;
    padding: 0;
    min-height: 0;
    height: calc(100% - var(--summary-height));
    overflow-y: auto;
    scrollbar-width: thin;
  }
  
  li {
    display: block;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;details open=""&gt;
    &lt;summary&gt;Details&lt;/summary&gt;
    &lt;ul&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
      &lt;li&gt;&lt;button&gt;&lt;img src="https://via.placeholder.com/64" alt=""&gt;&lt;/button&gt;&lt;/li&gt;
    &lt;/ul&gt;
  &lt;/details&gt;</code></pre>
  </div>
  </div>
  </p>
  <p>(<a href="https://jsfiddle.net/Pandraghon/yonj9s4w/" rel="nofollow noreferrer">JSFiddle</a> of the code above)</p>
  <p>Here's the code in its context: <a href="https://jsfiddle.net/Pandraghon/fhgsu596/16/" rel="nofollow noreferrer">JSFiddle</a></p>
  <p>Thanks in advance!</p>