title: Bootstrap select with BS4 input-group-prepend
body: <p>I am using bootstrap 4 and bootstrap select version 1.13.2 (latest), which should support bootstrap 4. As mentioned in docs, i even manually specified BS verison via </p>
  
  <pre><code>$.fn.selectpicker.Constructor.BootstrapVersion = '4';
  </code></pre>
  
  <p>I wanted to have an icon next to the picker, i used following markup</p>
  
  <pre><code>&lt;div class="form-group"&gt;
    &lt;div class="input-group"&gt;
      &lt;div class="input-group-prepend"&gt;
        &lt;div class="input-group-text"&gt;
          &lt;i class="fa fa-user"&gt;&lt;/i&gt;
        &lt;/div&gt;
      &lt;/div&gt;
      &lt;select id="internal-select-picker" class="form-control selectpicker" data-live-search="true" data-size="10" multiple&gt;
        &lt;option&gt;option 1&lt;/option&gt;
        &lt;option&gt;option 2&lt;/option&gt;
        &lt;option&gt;option 3&lt;/option&gt;
      &lt;/select&gt;
    &lt;/div&gt;                        
  &lt;/div&gt;
  </code></pre>
  
  <p>And the result is this, as you can see the icon is slightly larger than the select, i tried to apply different bs styles to both picker and icon group but nothing worked</p>
  
  <p><a href="https://i.stack.imgur.com/dTPQc.png" rel="noreferrer"><img src="https://i.stack.imgur.com/dTPQc.png" alt="enter image description here"></a></p>
  
  <p>Any suggestions how to resolve this issue will be appreciated</p>