JSFiddle - React, Tailwind, and code Playground
HTML
<select id='mySelect'></select>
CSS
#mySelect {
width: 100px;
}
JavaScript
document.getElementById('mySelect').onclick = loadOptions;
function loadOptions(e) {
setInterval(function () {
var o = document.createElement('option');
o.innerHTML = 'hello';
var newSize = e.target.size+1;
e.target.setAttribute('size', newSize);
e.target.appendChild(o);
}, 500);
}