JSFiddle - React, Tailwind, and code Playground

HTML

<div id="waitmessage"></div>

JavaScript

var SecondsToWait = 90;

var secInterval = setInterval(oneSecIntervalHandler,1000);

function oneSecIntervalHandler() {
    if (--SecondsToWait > 0) {
       $("#waitmessage").html( $("#waitmessage").html() + '.');
    } else {
        clearInterval(secInterval);
        //doAjaxStuffNow
        $("#waitmessage").html("doAjaxStuffNow...<br/>$.ajaxSetup( ...");
    }
    
}