JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://www.malsup.com/jquery/block/jquery.blockUI.js"></script>

JavaScript

$.blockUI({
    fadeIn : 0,
    fadeOut : 0,
    showOverlay : false
});

alert("Before AJAX");

$.ajax({
    type : 'POST',
    url : "/echo/html/",
    data: {
        delay: 10
    },
    async : false,
    success : function (returnData) {
    },
    error : function (xhr, textStatus, errorThrown) {
        //other stuff
    }
});

$.unblockUI();