title: Cannot Get Custom Dropdown to Work in QuillJS Editor
body: <p>Description: I'm having trouble creating a dropdown in the Quill Editor toolbar. Any help would be appreciated. Ideally, I want the dropdown to show up in the toolbar and add the select option text as text in the editor.</p>
  
  <p>Test Case: <a href="https://codepen.io/Graphettion/pen/OxezbO" rel="nofollow noreferrer">https://codepen.io/Graphettion/pen/OxezbO</a></p>
  
  <p>HTML</p>
  
  <pre><code>&lt;div id="editor-toolbar"&gt;
    &lt;select class="ql-emailVars"&gt;
      &lt;option value="1"&gt;Account Url&lt;/option&gt;
      &lt;option value="2"&gt;First Name&lt;/option&gt;
      &lt;option value="3"&gt;Login&lt;/option&gt;
      &lt;option value="4"&gt;Org Name&lt;/option&gt;
      &lt;option value="5"&gt;Support Email&lt;/option&gt;
    &lt;/select&gt;
  &lt;/div&gt;
  &lt;div id="editor"&gt;&lt;/div&gt;
  &lt;div class="text-output"&gt;&lt;/div&gt;
  &lt;div class="html-output"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>JS</p>
  
  <pre><code>const quill = new Quill('#editor', {
    modules: {
      toolbar: {
        container: "#editor-toolbar",
          handlers: {
            "emailVars": emailVars
          }
      }
    },
    theme: 'snow'
  });
  
  // Add Custom Dropdown to Toolbar
  function emailVars(args) {
    const value = args[0];
    const cursorPosition = this.quill.getSelection().index
    this.quill.insertText(cursorPosition, value)
    this.quill.setSelection(cursorPosition + value.length)
  }
  </code></pre>
  
  <p>Thank you,</p>