Demo of iframe shim. This will work using the standard object tag for videos but for iframe videos (YouTube) it will not. This is a Chrome issue only on Mac and PC.
Form validation test
https://github.com/Modernizr/Modernizr/pull/315#issuecomment-1871531
Spec: http://dev.w3.org/html5/spec/Overview.html#the-constraint-validation-api