JSFiddle - React, Tailwind, and code Playground

HTML

<div>Something</div>

JavaScript

$.expr[':'].icontains = $.expr.createPseudo(function( text ) {
    text = text.toLowerCase();
    return function (el) {
        return ~$.text(el).toLowerCase().indexOf( text );
    }
});

$(':icontains(SoMeThInG)').css('border', '4px solid green');