[csswg-drafts] [css-scroll-snap] snap points on pseudo elements

frivoal has just created a new issue for 
https://github.com/w3c/csswg-drafts:

== [css-scroll-snap] snap points on pseudo elements ==
In 
http://www.w3.org/mid/C65090CE-632C-4606-93A9-80F358A15510@rivoal.net,
 @tabatkins and I argued about snap points and pseudo elements. This 
was not resolved.

>>>but I'd also be in favor of making it apply to all pseudo elements.
 As long as something has a box, we should have all we need to make 
things work.

>>Yeah, but it has to be tree-abiding, or else it's unpredictable *how
many* snap-points it generates.  This rules out ::first-letter and
::first-line, as well as all the highlight pseudos like
::spelling-error.  This is the same reasoning that rules out
background-image and friends - it's unpredictable how many boxes the
pseudo-element will generate, as it depends intimately on the markup
it's applying to, and so we avoid any property that depends on or
visually exposes the number of boxes.

> I'm not sure I follow. While these pseudos do weird things to the 
tree
(making it no longer a tree), how do they create more than one box? Or
 do
you mean the boxes generated by their children? Why would that matter
for a snappoint?

> Also we do apply background image to non tree-abiding pseudos:
http://jsbin.com/nowose/edit?html,css,output

> I mean, yes, the non tree abiding pseudos are weird in general, and
there's all sorts of issues with them, but could you clarify a bit
what causes problems with regards to snap-points?

Please view or discuss this issue at 
https://github.com/w3c/csswg-drafts/issues/488 using your GitHub 
account

Received on Thursday, 15 September 2016 07:07:54 UTC