title: Hidden element won't copy to clipboard
body: <p>I am trying to add button to copy simple text string but without success. </p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>function kopiraj() {
    var copyText = document.getElementById("toCopy");
    copyText.select();
    document.execCommand("Copy");
    document.getElementById("telefon").innerHTML = 'Copied';
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;button type="button" onclick="kopiraj()"&gt;Copy&lt;/button&gt;
  &lt;input type="hidden" id="toCopy" value="123456789"&gt;
  &lt;p id="telefon"&gt;&lt;/p&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>It does not put anything in Clipboard.</p>
  
  <p>I do not need input field. I can add text in JS itself.</p>