JSFiddle - React, Tailwind, and code Playground
HTML
<form >
<input type="text" placeholder="coba isi atau kosongkan" required />
<input type="submit" value="kirim">
</form>
JavaScript
$('form input[type=text]').on('change invalid', function() {
var textfield = $(this).get(0);
// hapus dulu pesan yang sudah ada
textfield.setCustomValidity('');
if (!textfield.validity.valid) {
textfield.setCustomValidity('Tidak kosong!');
}
});