[whatwg] Simplified <picture> element draft

Bruno Racineux bruno at hexanet.net
Wed Jan 22 17:14:22 PST 2014

On 1/22/14 3:54 PM, "Adam Barth" <w3c at adambarth.com> wrote:

>The way we'd likely implement this feature in Blink is in couple
>stages.  In the first stage, we'd implement the portions of the
>specification that don't involve media queries because we'll be able
>to provide developers a high-quality implementation of that part of
>the spec, including preload scanning.  In the second stage, we'd
>implement the parts of the specification that relate to media queries.
> We'll likely wait to implement the second stage until we're able to
>provide a high-quality implementation, which means waiting until we're
>able to parse and process media queries in the preload scanner without
>joining the main thread.

Meanwhile, is there a way in which all vendors can prevent their
pre-loaders from preloading (and loading at all for that matter) any <img>
that has either: An html5 hidden attribute, or display:none; both inline
or via a css class in the head, which is the current behavior of the
<object> element in Webkit:

I think it's safe to say that, for the browser to load assets marked as
'display:none;' makes little sense, and overrides a developer's
ability to control when his/her assets are supposed to load.

Browsers loading stuff that's voluntarily set as hidden is a bad
performance predisposition, as well as a waste of bandwidth, especially
when it comes to responsive mobile sites where the context of hidden
*really* means hidden as in: Do *not* load unless actually displayed.


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