JSFiddle - React, Tailwind, and code Playground
HTML
<script src="https://raw.github.com/eduardolundgren/jquery-simulate/master/jquery.simulate.js"></script>
<button id='btn'>Click here to expand dropdown</button>
<select id='sel'>
<option>item 1</option>
<option>item 2</option>
<option>item 3</option>
<option>item 4</option>
</select>
JavaScript
$(document).ready(function() {
$("#btn").click(function() {
$("#sel").select().trigger('open');
});
});