JSFiddle - React, Tailwind, and code Playground

HTML

<li data-active="true">item 1</li>
<li data-active="false">item 2</li>
<li data-active="false">item 3</li>

JavaScript

console.log($($('li')[1]).data('active'));

$($('li')[1]).data('active', true);

console.log($($('li')[1]).data('active'));