JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    Email: <input type="email" id="email" name="email"><br/>
    Fornavn: <input type="text" name="firstname"><br/>
    Efternavn: <input type="text" name="lastname"><br/>
    </form>

JavaScript

$(function() {
    $("#email").blur(function(){
        alert("Her skal vi lave et AJAX kald");
    });
});