JSFiddle - React, Tailwind, and code Playground

JavaScript

function listingCallback(event) {
    if (this.readyState == 4 && this.status == 200) {
       console.log(this.responseText);
    }
}

window.setInterval(function() {
    var listingAjax = new XMLHttpRequest();
    listingAjax.addEventListener("load", listingCallback, false);
    listingAjax.open("POST", "/echo/html/", true);
    listingAjax.send('html=' + encodeURIComponent(JSON.stringify({foo:'bar'})));
}, 250);