JSFiddle - React, Tailwind, and code Playground

HTML

<button id="button">
Focus Me
</button>
<div id="status">
  Waiting...
</div>

CSS

button {
  background: unset;
  padding: 1em;
}

#console {
  position: absolute;
  top: 100px;
  left: 5px;
}

JavaScript

var button = document.getElementById('button');
var status = document.getElementById('status');

button.addEventListener('focus', function() { status.innerText = "focus" })
button.addEventListener('blur',function() { status.innerText = "blur" })

setTimeout(function() {
  button.disabled = true
}, 4000);