Looks good to me. @nwtn, you can abuse Modernizr.testStyles(str,fn) to create a fakeBody, so that the test doesn't require to be added below the head. html5shiv is using this technique (https://github.com/aFarkas/html5shiv/blob/master/src/html5shiv.js#L27-34) (injectElementWithStyles == Modernizr.testStyles)

Thanks, I'll take a look. My instinct is that it won't work because of the browser-find stuff that happens, but I hope I'm wrong.

Unfortunately, I can't get browser-find working with Modernizr.testStyles. Firefox is giving Component returned failure code: 0x80004003 (NS_ERROR_INVALID_POINTER) [nsIDOMWindow.find], even after a successful check for window.find. So, for now I think it'll have to stay like this.

I've noticed some other issues with how Opera is behaving, but that's a problem for another pull request.

thanks for the review and cleanup! :)