JSFiddle - React, Tailwind, and code Playground

HTML

Last url: <span id="last-url"></span><br>

<button id="next-url">Next URL</button><br>

<iframe id="site-frame" src="" style="width: 600px; height: 400px"></iframe><br>

JavaScript

// Random URLs from: https://github.com/jekyll/jekyll/wiki/sites

var urls = [
    "http://miloshadzic.com/", 
    "http://aganov.github.io/", 
    "http://bentzen.ws/"
]

$('#next-url').click(function() {
    var url = urls.shift()
    urls.push(url)
    
    $('#last-url').text(url)
    $('#site-frame').attr('src', url)
});