JSFiddle - React, Tailwind, and code Playground

HTML

<div id="content">
    <h1>Hello</h1>
    <ul>
   <li>List</li>
</ul>

<div id="tabs">
  <span>test</span>
</div>
</div>

JavaScript

var a = document.body.appendChild(document.createElement("a") );
a.download = "export.html";
html = "<html><head></head><body>" 
html += document.getElementById("content").innerHTML;
html += "</body></html>" 
a.href = "data:text/html," + html;
a.innerHTML = "[Download HTML]";