Make HTML5 form validation appear the same way in all recent browsers as Safari

safari-validate-popup.js

window.addEventListener('load', function(event) {
	// for each form on the page
	for(i=0; i < document.forms.length; i++) {
		f = document.forms[i];
		// add a 'submit' event listener
		f.noValidate = true;
		// except for safari, the event never triggers without noValidate=true
		f.addEventListener('submit', function(event) {
			// if form is not valid don't let it submit
			if(!event.target.checkValidity()) {
				event.preventDefault();
				alert('Form is not valid.');
			}
		}, false);
	}
}, false);