This app disables the submit button and enables after all required fields have been filled.
npm i @js-toolbox/js-disable-submit
<script src="https://cdn.jsdelivr.net/gh/homerocavazos/dsubmit@main/dsubmit.min.js"
integrity="sha384-RXWyNs/55QPKPWDP2rO/L2NxsGG0WH30v3+5mdN3IWZZY3qxO0mtxriXBTONKX/4" crossorigin="anonymous"></script>
Input elements must have a required attribute.
<input type="email" id="email" name="email" value="" required>
<script>
const example = new dSubmit();
example.init()
</script>