Unable to select multiple items on a muti select box
<p>I got a multiple select box as below</p>

<p>This is the HTML CODE</p>

<pre><code>&lt;select 
  name="bk_groupids" 
  id="bk_groupids" 
  multiple="multiple" 
  data-native-menu="false" 
  data-default-value=""&gt;
  &lt;option value='1'&gt;Ok&lt;/option&gt;
  &lt;option value='2'&gt;Ok1&lt;/option&gt;
  &lt;option value='3'&gt;Ok2&lt;/option&gt;
&lt;/select&gt;
</code></pre>

<p>When I click the button it turns blue as below but it is not showing all the items to select multiple.</p>

<p><a href="https://i.stack.imgur.com/kTSnj.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/kTSnj.jpg" alt="enter image description here"></a></p>

<p>How can I select multiple items from the select box?</p>

<p><strong>Update</strong></p>

<p>Just now noticed that we have to set <code>data-native-menu="false"</code>.  I just made the change and I got the error <code>Uncaught TypeError: a.preventDefault is not a function in jquery.min.js</code></p>