JSFiddle - React, Tailwind, and code Playground

HTML

<pre>
>abc
>def
>ghi
</pre>

<div></div>
<button type="button">Click Me</button>

JavaScript

$('button').click(function () {

  var val = $('pre').text(),
    regex = /(?:^>)(.+)(?:$|\n)/img,
    match = '',
    quote = [];

  while ((match = regex.exec(val)) !== null) {
    quote.push(match[1]);
  }

  $('div').html('<blockquote>' + quote.join('<br/>') + '</blockquote>');
});