Re: :stuck psuedo class WAS: specifying position:sticky

On Wednesday 2013-08-28 15:57 -0700, Tab Atkins Jr. wrote:
> On Wed, Aug 28, 2013 at 3:47 PM, Robert O'Callahan <robert@ocallahan.org> wrote:
> > On Thu, Aug 29, 2013 at 8:04 AM, Simon Fraser <smfr@me.com> wrote:
> >> The problem is that it defeats one of the main optimizations which drove
> >> our creation of a declarative sticky behavior, which is that we want to be
> >> able to delegate the implementation of the sticky behavior to another
> >> thread, the thread on which scrolling happens (keeping it off the main
> >> thread means that scrolling can remain responsive even when the main thread
> >> is busy doing layout/painting). If we have to do layout when an element
> >> enters or leaves the sticky state, then we’ll have to do that back on the
> >> main thread, which would result in a scrolling stutter.
> >
> > You could make the "stuck" state apply lazily, so scrolling wouldn't stutter
> > but a shadow (for example) would not appear or disappear immediately.
> 
> Similar to :hover, then?

How is it similar to :hover?  And under what conditions would the
style change take effect?

-David

-- 
𝄞   L. David Baron                         http://dbaron.org/   𝄂
𝄢   Mozilla                          https://www.mozilla.org/   𝄂
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