JSFiddle - React, Tailwind, and code Playground

HTML

<select id="test">
    <option>1</option>
    <option>2</option>
</select>
<div id="log">
</div>

JavaScript

var log = document.getElementById("log");

// Adding listener
var sel = document.getElementById("test");
sel.addEventListener("change", function(e){
    log.innerHTML += "Changed.<br>";
});

// Create event and fire it.
var changeEvent = document.createEvent("HTMLEvents");
changeEvent.initEvent("change",true,true);
sel.dispatchEvent(changeEvent);