JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/ui-lightness/jquery-ui.css">
<ul>
    <li><b>x</b></li>
</ul>

<button>click me</button>

JavaScript

/* Here's the original handler you can't access */

$('button').live('click', function(){
    $('ul').append('<li>Added item</li>'); 
});





/* Here's your handler */

$('button').live('click', function(){ 
    setTimeout( function() {
        $('ul li').not($('li b').closest('li')).append('<b> x</b>'); 
    }, 10);
});