Re: [cssom-view] Need to more clearly define the behavior of matchMedia

On Wed, 24 Sep 2014 02:34:18 +0200, Boris Zbarsky <> wrote:

> The spec for matchMedia is not very clear on two points:
> 1) When exactly "the associated media query list changes in evaluation".

I plan to fix this as part of making the 'resize' event synchronized with  
requestAnimationFrame, when the machinery for that is in place. It was  
pointed out on the telecon also that the above should happen when  
something causes layout to flush, although that itself is not really  

> 2) What should happen for display:none iframes.

HTML requires the iframe to have a 0x0 viewport. Does that cover it?

If a browsing context is not being rendered, it is expected to have a  
viewport with zero width and zero height.

> In practice, all three of Firefox, Safari, and Chrome have different
> behaviors on the attached testcase, though I'm about to make some
> changes to Firefox that will likely make it match Safari on this one
> specific testcase, more or less by accident.
> -Boris

Simon Pieters
Opera Software

Received on Thursday, 2 October 2014 07:29:57 UTC