JSFiddle - React, Tailwind, and code Playground
HTML
<ul id="myList" style="width: 150px;">
<li>itemitemitemitemitemitemitemitemitemitemitemitemitemitem</li>
</ul>
<div id="answer2"></div>
JavaScript
var totalHeight=0;
$("#myList li").each(function() {
totalHeight += $(this).outerHeight(true); // to include margins
});
$("#answer2").text("Answer 2: "+totalHeight);