JSFiddle - React, Tailwind, and code Playground
HTML
<div id='result'>empty</div>
<div id='other'>other</div>
JavaScript
var whatitis="Twoja firma / Twój biznes";
var whatitisnow = unescape(whatitis);
alert(whatitis);
alert(whatitisnow);
$('#result').append(whatitis+" changed to:"+whatitisnow);
$('#other').text(whatitis+" changed to:"+whatitisnow);