title: queryselector get elements where attribute starts with 'xxx'
body: <p>I am trying to get all items where the attribute starts with <code>comp-</code>. So, take this html for reference:</p>
  
  <pre><code>&lt;h1 comp-Color="red"&gt;Hello, world!&lt;/h1&gt;
  &lt;h1 comp-Background="black"&gt;Hello, world!&lt;/h1&gt;
  &lt;h1 comp-Age="123"&gt;Hello, world!&lt;/h1&gt;
  </code></pre>
  
  <p>I have tried doing this, but it doesn't seem to work:</p>
  
  <pre><code>let e = document.querySelectorAll('[^comp-]');
  </code></pre>
  
  <p>Doing so gives me the following error:</p>
  
  <blockquote>
    <p>Uncaught DOMException: Failed to execute 'querySelectorAll' on 'Document': '[^comp-]' is not a valid selector.</p>
  </blockquote>