title: DOMPDF How to get CSS Content :before rendered?
body: <p>In DOMPDF I have a problem, rendering content, which is set with CSS Attribute :before and content</p>
  
  <p>I have a span:</p>
  
  <pre><code> &lt;span class="marker" position="1"&gt;
  </code></pre>
  
  <p>And the CSS</p>
  
  <pre><code>  .marker::before {
      content: "[" attr(position) "]";
  </code></pre>
  
  <p>But it does not appear in the DOMPDF Output.</p>
  
  <p>What can I do ?</p>