title: Not able to add attribute like Id or class for any tag in trix-editor while inserting HTML programmatically
body: <p>I am trying to add attribute like id, class for span tag in trix-editor while inserting the html through java-script but when I checked the DOM for that tag, editor removing the added attributes from tag. </p>
  
  <p>My Java-script code to insert html with attribute:</p>
  
  <pre><code>element.editor.insertHTML("&lt;span id='" + userId + "' class='mention-user'&gt;" + userName + "&lt;/span &gt;"); 
  </code></pre>
  
  <p>DOM:</p>
  
  <pre><code> &lt;div&gt;&lt;!--block--&gt;@&lt;span style="font-size: 12px;"&gt;abc/span&gt;&lt;/div&gt;&lt;/trix-editor&gt;
  </code></pre>
  
  <p>Even I have tried:</p>
  
  <pre><code>element.editor.activateAttribute("href", "https://trix-editor.org/");
  </code></pre>
  
  <p>this is working fine but not able to add id or class. can anybody have an idea to add id or class in tag?</p>