Re: [css-will-change] establishing containing block for fixed-positioned elements

On Friday 2015-12-04 16:27 -0800, Tab Atkins Jr. wrote:
> On Fri, Dec 4, 2015 at 4:14 PM, L. David Baron <dbaron@dbaron.org> wrote:
> > On Friday 2015-12-04 16:07 -0800, Tab Atkins Jr. wrote:
> >> Why do you think that abspos-CB generators don't need to be handled?
> >
> > Because the only abspos-CB generated that's not also a fixpos-CB
> > generator is (I think) 'position', and I don't think there's much of
> > a use case for 'will-change: position'.
> >
> > (Does anyone really want to rapidly toggle between absolute and
> > relative positioning at 60 Hertz?)
> 
> Well, between absolute and static. Relpos makes a CB. ^_^
> 
> Point isn't necessarily to make it possible to toggle rapidly (tho
> that's part of it), it's to minimize unrelated visual jumps by making
> the states more similar in their wide-ranging behavior.

OK, I filed https://bugzilla.mozilla.org/show_bug.cgi?id=1230701 to
implement this behavior.  (Probably won't get to it for a bit,
though.)

-David

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