JSFiddle - React, Tailwind, and code Playground

HTML

<div id="display"></div>

JavaScript

var display = document.querySelector('#display');
var prev = 0;
function pad(v) {
    return ('0' + v).slice(-2);
}
function update() {
    var now = Date.now() / 1000 | 0;
    if (now > prev) {
        prev = now;
        var date = new Date(now * 1000);
        console.log(date); // spam spam... well, just once per second
        display.innerHTML = pad(date.getHours()) + ':' + pad(date.getMinutes()) + ':' + pad(date.getSeconds());
    }
    window.requestAnimationFrame(update);
}
update();