title: css `<tag>:has(+ <tag>)` is not applied
body: <p>Here is the intended behavior:</p>
  <p>For each element with a class <code>.inline-s-collapsible</code> of which the previous element is a p tag, apply the styling to the p tag.</p>
  <p>And here is my code:</p>
  <pre><code>p:has(+ .inline-s-collapsible) {
      display: inline-block !important;
      background-color: red !important;
  }
  </code></pre>
  <p>Why isn't it working?</p>
  <p><a href="https://jsfiddle.net/e6dxzo5g/" rel="nofollow noreferrer">https://jsfiddle.net/e6dxzo5g/</a></p>
  <p>It should work: <a href="https://drafts.csswg.org/selectors-4/#relational" rel="nofollow noreferrer">https://drafts.csswg.org/selectors-4/#relational</a></p>