<!DOCTYPE html> <html class="reftest-wait"> <!-- Test: if input is readonly, it is barred from constraint validation and should not be affected by :invalid pseudo-class. --> <link rel='stylesheet' type='text/css' href='style.css'> <body onload="document.getElementById('i').readOnly='ro'; document.documentElement.className='';"> <input class='notinvalid' id='i' required> </body> </html>