JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="topnav">
    <li>Item 1</li>
    <li>Item 2 
        <ul><li>Nested item 1</li><li>Nested item 2</li><li>Nested item 3</li></ul>
       </li>
    <li>Item 3</li>
</ul>
<div>DIV1</div>
<div>DIV2</div>
<span>SPAN</span>
<table>
<tr>
    <td>Username</td>
</tr>
<tr>
    <td>Password</td>
</tr>
</table>
<p>
  <input type="checkbox" name="remember" tabindex=3 />
  <label for="checkbox">Remember <strong>password</strong></label>
</p>
<p>Click here to <a href='register.php'>Register</a></p>

JavaScript

$('*').contents().filter(function() {
    return this.nodeType == Node.TEXT_NODE && this.nodeValue.trim() != '';
}).each(function() {
    this.nodeValue = '@@@@';
});

alert($('html').html());