title: Disable details/summary
body: <p>When I use the new <code>details</code> tag in combination with a <code>summary</code> I would then like to disable the generated input. I thought that</p>
  
  <pre><code>&lt;details open disabled&gt;
  </code></pre>
  
  <p>could do the trick, but sadly it doesn't work.</p>
  
  <p>How can one disable the details element?</p>