title: Picture Tag Using data-srcset Instead of srcset
body: <p>I'm currently validating my HTML and am getting errors because my picture tags uses data-srcset instead of srcset. My question is, if I'm using data-srcset do I HAVE to use the srcset attribute for valid HTML? It would seem so.</p>
  
  <p>Example:</p>
  
  <pre><code>&lt;picture&gt;
    &lt;source data-srcset="assets/media/images/attorneys/img-attorney.webp" type="image/webp"&gt;
    &lt;source data-srcset="assets/media/images/attorneys/img-attorney.png" type="image/jpg"&gt;
    &lt;img src="assets/media/images/attorneys/img-attorney.png" class="lazy" alt="Attorney"&gt; 
  &lt;/picture&gt;
  </code></pre>