OptinMonster, validation to require first/last name

om-validate-first-last-name.js

<script>
document.addEventListener('om.Campaign.afterShow', function(event) {
	var campaign = event.detail.Campaign;
	if ( '{{id}}' !== campaign.id ) {
		return;
	}

	var validationError = 'A last name is required.';

	var $nameField = document.getElementById( '{{ns}}-field-name' );
	var $btn       = document.getElementsByClassName( '{{ns}}-field-submit' )[0];

	function nameValidates() {
		// Make sure there are 2 distinct names.
		return $nameField.value.search(/^[a-z,.'-]+ +[a-z,.'-]+$/i) >= 0;
	}

	$btn.disabled = true;
	$nameField.addEventListener( 'keyup', function() {
		$btn.disabled = ! nameValidates();
	} );

	$nameField.addEventListener( 'blur', function() {
		campaign.Form.resetValidation()
		if ( ! nameValidates() ) {
			campaign.Form.errors.validate.push(validationError)
			campaign.Form.showValidateErrors()
		}
	} );
});
</script>