title: Bootstrap 4 Beta: Options Menu has double dropdown icons
body: <p>I have an issue with the way Bootstrap makes my options menu visualize. Check out the screenshot:</p>
  
  <p><a href="https://i.stack.imgur.com/LLxcF.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/LLxcF.png" alt="enter image description here"></a></p>
  
  <p>I don't know what is the reason for this. I am not using labels in this particular case but they don't help either.</p>
  
  <p>This is the code:</p>
  
  <pre><code>        &lt;nav class="sidebar col-sm-4 col-md-3 d-inline align-self-auto"&gt;
          &lt;div class="form-group"&gt;
              &lt;select class="custom-select mt-2"&gt;
                  &lt;option selected&gt;Марка&lt;/option&gt;
                  &lt;option value="1"&gt;БМВ&lt;/option&gt;
                  &lt;option value="2"&gt;Рено&lt;/option&gt;
                  &lt;option value="3"&gt;Форд&lt;/option&gt;
              &lt;/select&gt;
  </code></pre>
  
  <p>Please help me with this one as I want a great looking website.
  I am using Bootstrap 4.0.0.b
  I should also mention I am using gulp to compile my CSS.</p>
  
  <p>Thanks in advance.</p>