JSFiddle - React, Tailwind, and code Playground
HTML
<script>
function dialog() {
document.getElementById('result').src = "http://jsfiddle.net";
}
function loading() {
alert(23);
document.getElementById('loading').style.display = "none";
document.getElementById('result').style.display = "block";
}
</script>
<div id="loading">Loading</div>
<iframe style="display:none;" id="result" onload="loading();" src="http://jsfiddle.net"/>