Re: [css3-regions] regions forming stacking contexts

On Fri, Feb 3, 2012 at 8:07 PM, Vincent Hardy <vhardy@adobe.com> wrote:

> Regarding the initial containing block, I am not sure what is missing from
> the spec. can you clarify? Section 4.1 is explicit:
>
> "The edges of the first region in a region chain associated with a named
> flow establish the rectangle that is the initial containing block of the
> named flow."
>
> So why do you think the positioning of absolute elements in undefined in
> the specification?
>

Oh, I didn't realize you were redefining the ICB with the intent of
modifying the positioning spec. That does make it a bit clearer, but ...

Currently in CSS, the ICB is defined as "The containing block in which the root
element <http://www.w3.org/TR/CSS2/conform.html#root> lives". There is only
one per document, which is why the specs always refer to "*the* initial
containing block". You are implicitly redefining the ICB to be something
that can be different for different elements (or possibly boxes, I'm not
sure), which is actually a nontrivial change to CSS. Such a change really
needs to be called out, may have unintended consequences, and possibly
doesn't belong in Regions spec. We'd also need to audit all specs to make
sure that when they refer to "the initial containing block", it's clear
which elements' ICB they're referring to. It may actually be easier to do
what you want by some other means.

Rob
-- 
"If we claim to be without sin, we deceive ourselves and the truth is not
in us. If we confess our sins, he is faithful and just and will forgive us
our sins and purify us from all unrighteousness. If we claim we have not
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