JSFiddle - React, Tailwind, and code Playground

by southerd

HTML

<form>
    <input type="email" value="notAnEmail" required />
    <input type="submit" />
</form>

JavaScript

var input = document.getElementsByTagName('input')[0];
input.setCustomValidity("Nope");

var form = document.getElementsByTagName('form')[0];

console.log(input.validationMessage);
console.log(form.checkValidity());