按下按钮时，在修改DOM之前复制原始HTML代码

Question

我需要在点击按钮时复制HTML代码。在我们使用video标记的地方，该功能无效。 video标记以某种方式被brightcove格式化。我尝试使用<pre>和<code>元素。能否请你提出建议。

$('.copy').on('click', function() {
  var section = $(this).next().find('code').html();
  var elem = document.createElement('textarea');
  //elem.textContent = section;
  elem.innerHTML = section;
  //elem.classList.add('invisible');
  document.body.appendChild(elem);
  console.log(elem.innerHTML);
  elem.select();
  console.log("Hi");
  try {
    document.execCommand('copy');
  } catch (e) {
    console.log('ERROR: ' + e);
  } finally {
    elem.remove();
  }
});

<div class="ply-item-ratio-content">
  <!-- Start of Brightcove Player -->
  <div class="parbase brightcovevideo section">
    <div style="margin-bottom: 0;margin-left: 0;margin-right: auto;margin-top: 0;overflow-x: hidden;overflow-y: hidden;text-align: center;width: 1025px;text-align:left; height: 560px;">
      <div id="25efba484"> </div>
      <script type="text/javascript" src="/etc/polycom/www/global/js/thirdparty/BrightcoveExperiences_embedded.js"></script>
      <script>
        customBC.createVideo("1000", "567", "4223245001", "cd~~,AddB-EKwxDE~,eUqCcdvdv7u6CqAyJC", "4435446654001", "2768ede1a35dsgfdgffba484");
      </script>
    </div>
  </div>-->
  <!-- End of Brightcove Player -->
</div>
</div>
<div class="ply-global-video-description">
  <h2>NATO Communications and Information (NCI) Agency Success Story</h2>
  <p>Centro to create a relaxed working environment that draws teams closer together and enables better sharing of ideas and insights.</p>
</div>
</div>