- From: Ian Hickson <ian@hixie.ch>
- Date: Mon, 10 Mar 2014 19:47:59 +0000 (UTC)
- To: Yoav Weiss <yoav@yoav.ws>
- Cc: whatwg <whatwg@lists.whatwg.org>, Boris Zbarsky <bzbarsky@mit.edu>
On Tue, 7 Jan 2014, Yoav Weiss wrote: > On Tue, Jan 7, 2014 at 6:20 PM, Boris Zbarsky <bzbarsky@mit.edu> wrote: > > On 1/7/14 12:01 PM, Yoav Weiss wrote: > > > >> I'd love to get some more details regarding that. I'll start a > >> mozilla.dev.platform thread on the subject, since it's Gecko > >> specific. > > > > It's actually not entirely Gecko-specific. > > > > Consider a display:none iframe. How should viewport-size-related > > media queries be evaluated in such a thing? The specs don't define > > it, as far as I can tell. In fact, the specs don't actually define > > anything useful for the viewport of a framed document at all, as far > > as I can see. CSS just assumes a viewport exists, and HTML doesn't > > define anything about frames setting up a viewport for the document > > inside them... > > > > But say they defined it. How would the viewport of a display:none > > iframe be defined, exactly? > > > > Last I checked, UAs just end up doing wildly different things in this > > situation. > > I agree that iframes complicate things, since the parent document's > external CSS can modify their viewport dimensions, so there's an > inherent race condition there. It's sort of a race, but it settles, right? > Since this case is not the majority case, we could bail out of it by > delaying the iframe's subresource loading that rely on viewport > dimensions until the parent's layout is considered "done" (e.g. all its > <head> CSS was parsed and applied) The <iframe> can change dimensions long after that, still (e.g. if it's sized based on other content later in the page, as in a complex table). I'm sure browsers can optimise a bit here, but it's not clear to me that there's anything we need to explicitly require. -- Ian Hickson U+1047E )\._.,--....,'``. fL http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,. Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
Received on Monday, 10 March 2014 19:48:28 UTC