JSFiddle - React, Tailwind, and code Playground

HTML

<div class="doit" style="color:green">This text should be replaced (a)</div>
<div class="doit2" style="color:red">This text should be replaced (b)</div>

JavaScript

a();
function a() {
    $('.doit').text('Text was replaced (a)');   
}

if ($('.doit2').length) {
    b();
    function b() {
         $('.doit2').text('Text was replaced (b)');   
    }
}