JSFiddle - React, Tailwind, and code Playground

HTML

<div class="div1"></div>
<div class="div2"></div>

CSS

* {
  margin: 0;
  padding: 0;
}
.div1 {
  width: 100vw;
  height: 100px;
  line-height: 100px;
  text-align: center;
  color: red;
  overflow-y: scroll;
  border: 1px solid #000000;
  margin-bottom: 15px;
}
.div2 {
  width: 100vw;
  height: 100px;
  line-height: 100px;
  text-align: center;
  color: green;
  overflow-y: hidden;
  border: 1px solid #000000;
  margin-bottom: 15px;
}

JavaScript

var w1 = $('.div1').width();
var w2 = $('.div2').width();

$('.div1').html(w1);
$('.div2').html(w2);