title: TypeError: popper is null
body: <p>My problem: when i click on the dropdown, i have an error message in my console:</p>
  
  <p><a href="https://i.stack.imgur.com/A15Y9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/A15Y9.png" alt="enter image description here"></a></p>
  
  <p>An extract of my twig:
      
      </p>
  
  <pre><code>&lt;select class="tabledit-input form-control dropdown-toggle" data-toggle="dropdown" name="color" &gt;
      {% for item in items %}
          &lt;option value="{{ item.id }}" selected=""&gt;{{ item.Label }}&lt;/option&gt;
      {% endfor %}
  &lt;/select&gt;
  &lt;button type="button" class="btn btn-success validbtn"&gt;Valid&lt;/button&gt;
  </code></pre>
  
  <p></p>
  
  <p>I check in my package.json and in the app.js and everything is ok. I have read that it could be link to the data-toggle="dropdown".But i don't know where is the error. </p>
  
  <p>I don't know if it's important but this select is in a cell of a datatable.</p>