[CSSWG] Minutes Telecon 2018-02-28 [css-multicol] [css-fonts-4] [css-backgrounds] [css-values] [typed-om]

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CSS Multicol
------------

  - RESOLVED: column-gap: normal computed value returns normal
  - There were three options available for Issue #2309 (Column rules
      should only be drawn to the height of the column contents)
      1) make a user control so people can explicitly control height
         of column rules to be that of the content height or the
         multicol height
      2) Stay with current spec which suggests height of column rules
         is the same as the multicol element height
      3) Height of the column rule is based on height of the content
         of the multi-height

Fonts 4
-------

  - RESOLVED: No change for issue #2304 (font-variant-emoji: Consider
              broadening to all "color fonts" use-cases, not just
              emoji PPCP)

CSS Backgrounds
---------------

  - RESOLVED: Switch the order to match current implementations on
              issue #2305 (Change canonical serialization for
              box-shadow)

CSS Values
----------

  - RESOLVED: Accept the proposal in #2337 (calc() should round when
              it's used as an <integer>)

CSS Typed OM
------------

  - TabAtkins plans on making edits for Houdini issue #716 (Trim
      CSSResourceValue and subclasses to opaque objects for this
      level, punt rest to level 2) this week so requested anyone
      interested add their thoughts to the github.

===== FULL MINUTES BELOW ======

Present:
  Rossen Atanassov
  Tab Atkins
  David Baron
  Amelia Bellamy-Royds
  Tantek Çelik
  Dave Cramer
  Alex Critchfield
  Benjamin De Cock
  Tony Graham
  Dael Jackson
  Brad Kemper
  Vladimir Levantovsky
  Peter Linss
  Anton Prowse
  Liam Quin
  Manuel Rego
  François Remy
  Melanie Richards
  Alan Stearns
  Eric Willigers

Regrets:
  Elika Etemad
  Florian Rivoal
  Lea Verou
  Sergio Villar Senin
  Greg Whitworth

Scribe: dael

Reminders and Agenda
====================

  Rossen: It is a few minutes past.
  Rossen: As usual, any extra agenda items?
  Rossen: I had a couple of quick items.
  Rossen: First is a reminder that if you haven't booked your Berlin
          travel it's time to do it now.

  Rossen: Other topic which is related to the F2F/TYPO is the CSSWG
          talk/presentation/whatever.
  Rossen: Correct me, but my understanding is we have about an hour.
          There was a request on the private list for ideas/topics.
  Rossen: Please take a look. Make suggestions. Volunteer.
  Rossen: I proposed a quick structure but I'm just throwing ideas out
          there.
  Rossen: I'm expecting people to suggest other things.
  Rossen: Please look.

  Rossen: The other thing is we have fallen back on our spec rec push.
  Rossen: We want to resume the focus on the spec getting close to pr
          and rec.
  Rossen: I started/resumed the private list thread. I won't take time
          on the call to review but please take a look and update if
          you have any actions or tasks.
  Rossen: Let's try to move things forward.
  Rossen: We need myles for fonts so we'll postpone until he joins.

Border width rounding clarification
-----------------------------------
  github: https://github.com/w3c/csswg-drafts/issues/2114

  Rossen: Is dbaron or fantasai able to summarize?
  dbaron: I could attempt to, but I'm not sure why it's agenda+. It's
          a long issue and I"m not sure what fantasai wanted group
          opinion on.
  Rossen: I'm fine postponing until fantasai joines the call. We can
          ask her.

CSS Multicol
============

Gutter properties computed value
--------------------------------
  github: https://github.com/w3c/csswg-drafts/issues/2294

  Rossen: Summary is we have column-gap:normal value return as 0px for
          anything that's not a multi-column and 'normal' if it is a
          multicol
  Rossen: Issue raised by Igalia that getComputedStyle where all
          browsers but edge return normal. Proposal was to make
          computed value to be normal everywhere.
  Rossen: The consensus on the issue seems to be normal computes as
          normal.
  Rossen: So I'm looking for feedback or other idea.
  Rossen: Should we just adopt proposed resolution or not change?
  Rossen: Does anyone care about this who is on the call?

  tantek: Only thing I'd add is just +1 to Mats.
  Rossen: What he's saying is common sense of not making style depend
          on layout and not make properties depend on other properties
          which is one of our guiding rules and I fully agree. Just
          curious on this issue.
  rachelandrew: I agree with fantasai that people who care will
                specify anyway so if impl are happy to go with normal
                that makes sense.
  Rossen: I don't think we'll have a problem changing to normal. I
          think we're the only implementation that returns 0. I'm
          assuming given all other implementors return normal there
          shouldn't be a compat risk for us, or at least minimal.

  tantek: Looking quick I didn't see a simple dom test to check
          current impl. I'd be curious to try it in other browsers to
          see if there is anything consensus-wise.
  Rossen: Right.
  tantek: Can I request that before we resolve? To add a test to get
          information?
  Rossen: Absolutely. We don't have to resolve today. fantasai and
          florian are out. They and Sergio are active. I'm just
          looking for progress.
  Rossen: Sounds like we want examples and test cases to eval other
          impl.
  tantek: At least to inform the decision better. Sounds like rough
          consensus but it's based on theoretical purity.
  tantek: I'd like more concrete data.
  rego: There's WPT tests for this. That's why I realized Edge isn't
        returning normal and that's when I checked the specs.
  tantek: Can you add a link to it?
  <rego> http://w3c-test.org/css/css-align/gaps/column-gap-parsing-001.html
  rego: ^
  tantek: Thanks.
  <tantek> rego which of the tests?
  <tantek> (of the 17)
  <rego> the first one "Default column-gap is 'normal'"
  <rego> in Edge it fails
  <rego> I meant, it returns 0px
  Rossen: I see the same behavior as rego stated in the issue. In
          windows I see Edge report 0 and FF and Chrome return
          'normal'.
  tantek: There's 17 tests.
  rego: First one is the one that fails.
  Rossen: fwiw looking at IE I think we regressed this in edge
          unintentionally.
  Rossen: For the sake of argument this could be just a bug.
  tantek: I see normal in FF & Chrome
  <rego> and Safari
  Rossen: Yeah. That's what I said. Normal everywhere, FF, Chrome, IE
          11. Edge is only one that does 0.
  tantek: Safari also.
  tantek: Okay. That makes it pretty clear.

  Rossen: Going back to the issue, is this something we want to punt
          or do we feel there is enough understanding to resolve?
  tantek: I think there's enough understanding.
  tantek: If fantasai or anyone else has new information we can follow
          our normal procedure.
  Rossen: fantasai supports normal to normal in the issue.
  Rossen: Objections to resolving that column-gap: normal computed
          value returns normal?

  RESOLVED: column-gap: normal computed value returns normal

Column rules should only be drawn to the height of the column contents
----------------------------------------------------------------------
  github: https://github.com/w3c/csswg-drafts/issues/2309

  Rossen: This came from dbaron a couple weeks ago and added by
          rachelandrew.
  <Rossen> test case:
https://w3c-test.org/css/css-multicol/multicol-breaking-001.html
  dbaron: There was a thing in the spec, I had been doing testing and
          it didn't match FF and Chrome and didn't make sense to me.
          Edge does impl what the spec says. Question is what happens
          to column rules when content of columns doesn't fill the
          space it could fill.
  dbaron: Either because you have a multi-col with a spec width and
          height unspec # col. Depending on column-fill balance|auto
          you might have content in the first and second or the top of
          the first. Question is where do you draw the rules.
  dbaron: Spec says a full height rule between any pair with content
          in them. Completely empty is no rule. THat's not what FF and
          Chrome do. Last comment in GH issue I linked to a test.
  dbaron: I think it...don't look in FF, look in Chrome and Edge.
  Rossen: I'm assuming you're going to be fixing in FF, that's why
          you're looking?
  dbaron: Wait a moment...I think I've gotten things confused.
  dbaron: FF has a bunch of other bugs here that are messing this up
          in weird ways.
  dbaron: What this test shows is a multicol inside another.
  dbaron: Spec calls for the purple column to go all the way tot the
          bottom in the second column. FF & Chrome only take it to the
          bottom of the content.
  Rossen: What is wrong with this? I believe what the spec suggests in
          terms of behavior as well as what IE/Edge/Presto impl for
          column rules makes a lot of sense.
  Rossen: Are you suggesting only make app column rules only draw to
          content type?
  dbaron: That's what I'm suggesting. I made that suggestion before
          testing edge so I made it before realizing current browsers
          did the thing the spec said.

  dauwhe: I prefer Chrome to the spec
  dauwhe: Purely as a visual thing, having the rule extend past empty
          space strikes me as unexpected.
  plinss: I think it should be an author rule. Having rules only to
          content seems common, but you might want rules to go all the
          way when you're doing something sophisticated. If you're
          going to content you should make sure all rules are to the
          same length.
  dbaron: Might makes sense for balancing, but not column fill auto.
  dauwhe: I agree with plinss about author control though.

  <AmeliaBR> Does anyone have the current spec text? Is it really
             supposed to apply to columns inside columns?
  Rossen: To answer AmeliaBR, columns inside of columns brings nothing
          interesting. dbaron did it for illustrative purposes to show
          when the multicol itself is the content of another column
          what the behavior is.
  <dbaron> AmeliaBR, the spec text is quoted in the first comment of
           the issue
  * AmeliaBR thanks dbaron
  Rossen: In this case I would have expected that...if we have content
          height as the limit to column gaps, what Chrome does is the
          behavior which would be compliant. And if column rules are
          used to show where columns are and their height, because as
          dbaron illustrates when you have a background you'll see the
          heights, that looks just as silly as the other way where you
          don't have the BG but you have the rule.
  Rossen: I sympathize to plinss's suggestion of an author control.
          Having the background & the column rules not be the same
          height is pretty silly. That's my personal opinion.
  Rossen: It seems strange that the two are not going hand in hand.
  AmeliaBR: I brought it up because it seems browsers are consistent
            with outer level being full height. It's only when you add
            the inner level and how it break across multiple it's weird
  Rossen: The multicol inside the top level extends all the way down.
          That's why the rules are they way they are. It is visually
          deceiving.
  Rossen: In this case if you had max-height on the inner and height
          on the outer so it stretches beyond I would expect column
          rules to be the same height
  <dbaron> I'd note that if you remove the .outer { column-fill:
           auto } in the testcase than the thick blue rules get shorter

  liam: There's a danger here that...in trying to decide based on
        weird test cases. If I had spec a height explicitly I'd expect
        the rule to go all the way down. Either you want a control as
        plinss said or it should honor the height if you gave one.
        Maybe you need to look at actual use cases.
  Rossen: Now you're suggesting tie in column height and rule
          properties which goes against our groups.
  liam: No no, I'm asking what is user's expectation. If you have an
        area with the height and column rules chances are you want the
        rules all the way down. I'm supporting a property.
  Rossen: I can't speak for the billions of users of the web. From a
          pure layout PoV what I said is if you have column boxes with
          backgrounds that extend the rules should extend the same
          way. That's consistent with other properties.
  <dbaron> I think this was also a case where this was implemented in
           browsers *before* the current spec text existed.

  Rossen: Let's see if we can narrow down this issue and get to
          something actionable.
  Rossen: Current proposal a 1) make a user control so people can
          explicitly control height of column rules to be that of the
          content height or the multicol height
  Rossen: 2) Stay with current spec which suggests height of column
          rules is the same as the multicol element height
  Rossen: 3) Height of the column rule is based on height of the
          content of the multi-height
  Rossen: We can try to make a resolution or we can stop discussing
          here and continue on GH. Get user feedback from designers,
          come back and see what stands out.
  Rossen: Preference dbaron?
  dbaron: I'm fine discussing more.
  Rossen: Okay.

CSS Fonts 4
===========

font-variant-emoji: Consider broadening to all "color fonts"
    use-cases, not just emoji PPCP
------------------------------------------------------------
  github: https://github.com/w3c/csswg-drafts/issues/2304

  myles: This topic was discussed a few weeks ago but a commenter
         brought up new points. Because previous issue was resolved we
         moved to a new issue. So just the new parts.
  myles: This is a property that renders characters as if they have
         variation selectors. This property sets the default so if you
         don't have a selector CSS can say emoji or text style.
  myles: Question was if this property should effect color fonts.
  myles: Color font formats have been increasingly common. The request
         was...the CSS should be able to turn those on and off.
  myles: That's the background. Anything anyone wants to say before I
         give an opinion?
  myles: Should we allow the selector to affect regular color fonts?

  myles: I haven't heard an author say they used color fonts
         accidentally. Person raising this hasn't brought a case where
         this is needed, just that it's easy to implement.
  myles: I haven't heard an author need. Also there isn't full interop
         on variation selectors and if we added more semantics it
         would limit our ability to standardize. This issue is not
         motivated and would hinder standardization.

  <tantek> uh, turning off color (or picking different contrasts) is a
           pretty accepted a11y use-case
  <liam> +1 to tantek but not clear that's at the font level but at
         the UA level overall

  AmeliaBR: On the question of is there a use case. When it comes to
            color web fonts I don't think anyone is using and wanting
            to turn them of fin general. When it comes to native
            emojis there is an issue where we have inconsistency as to
            how to handle interaction of fill and stroke with a native
            color font like and emoji.
  AmeliaBR: As color fonts become more common it might be useful to
            use a font consistently but turn off the color for certain
            elements. But I don't have as much of a use case as I do
            for the emoji.
  myles: That's a good point. It is important that we should spec
         interaction between fill/stroke and the color fonts.
  myles: This proposal could go 2 ways. Way #1 is this would affect
         font selection and you'd just turn off the color parts.
         Option #2 is when you select font you skip the color. This
         was about option 2 but it sounds like you're interested in 1.
  myles: Main concern with turning off tables in the font file is 1)
         that we don't have a precedent. 2) is if they want the color
         to work it's possible using 2 of the font formats.
  myles: Lastly color is part of the design of these fonts. If you
         took the color out it would hamper the design and the font
         would be useless. I list fonts in the issue where you can't
         remove the color. It would be unfortunate for users to...it
         would lead to confused users.
  AmeliaBR: Many of these color fonts are shipping with fallback plain
            outlines. But some aren't. If the font has a built in
            monochrome fallback it seems logical to allow web page
            authors a way to access it. If there is no fallback
            logical is to fallback to a different font. It's hard to
            integrate both into the font selection algorithm.
  myles: Yeah and this is a case where the browser should be in the
         business of looking at the outline and say if it should be
         able to be used.
  myles: And the fallback is required, there has to be a table. But
         the contents may be empty or garbage.
  <Rossen> +1 to what myles said
  Rossen: I agree with myles. I want to see if there are any other
          options or idea.
  <fremy> @myles: just throwing a random idea here, how about we
          render the glyph, convert to grayscale, and use this an
          opacity mask on a background of the color of the "color"
          property?

  Rossen: From IRC I want to voice tantek's point about this being a
          a11y lever. I agree with liam this shouldn't be the thing of
          font selection. We normally handle high contrast etc. on a
          much higher level for style or a lower level for color
          inversion.
  <tantek> Rossen: TBH it's both system level and app/site level. e.g.
           both mobile OS's and mobile sites have "night mode"
           features that alter such things

  Rossen: Back to myles what do you want to do?  Close no change?
  myles: Right.
  Rossen: Any objections or alternative proposals?
  AmeliaBR: If we close no change we keep this property that will only
            effect on the specific unicode characters designated as
            having plain text or emoji presentation?
  myles: Right
  AmeliaBR: And it would effect font selection to render those
            characters?
  myles: It might. That's why I phrases the property as I did. In Mac
         and iOS it does. I believe on every platform it might effect
         font selection.
  Rossen: Does that answer you AmeliaBR?
  AmeliaBR: Pretty much. I still agree it would be nice to have a
            toggle to turn off color font on generic text but I
            realize right now use cases aren't clear.
  myles: If a web author wants to turn off color font they should
         remove it from the font family list.
  AmeliaBR: I think we need to wait in see how things like font
            variations and ways to work with existing font files. Like
            people making color and monochrome and swapping between
            the two. It's still hypothetical.
  myles: That tech doesn't exist for any font format right now.
  Rossen: Okay, objections to resolve no change?
  Rossen: If there are more compelling use cases or additional
          information we'll of course reconsider.

  RESOLVED: No change for issue #2304

CSS Backgrounds
===============

Change canonical serialization for box-shadow
---------------------------------------------
  github:  https://github.com/w3c/csswg-drafts/issues/2305

  TabAtkins: Going by standard rule that default serialization should
             match grammar that implies color after link but impl does
             color before links. We should change grammar to match
             impl.
  Rossen: Looks like edits were pushed out. So only thing we need to
          do is get consensus.
  Rossen: Any other opinions as to why we shouldn't do this?
  <dbaron> This is part of why I am not a fan of that general rule
           being imposed without doing compatibility testing first...
           although I think we may have rolled back the rule a bit?
  <bradk> +1
  <AmeliaBR> +1 to matching reality & also other properties
  Rossen: Objections to switch the order to match current impl?

  RESOLVED: switch the order to match current implementations

CSS Flex
========

Min-content sizing currently too smart to be web compatible?
------------------------------------------------------------
  github: https://github.com/w3c/csswg-drafts/issues/2353

  TabAtkins: I need to review this with fantasai
  fremy: Then I can introduce it before next week
  fremy: We tried to update Edge to follow spec for flex-basis. A lot
         of websites if you spec width or height even if there isn't
         content it's respected for min-content sizing.
  fremy: We probably don't want to change this alone or first. Let's
         discuss next week.

CSS Values
==========

calc() should round when it's used as an <integer>
--------------------------------------------------
  github: https://github.com/w3c/csswg-drafts/issues/2337

  TabAtkins: Basic issue, when you put an invalid number in the calc
             due to range restrictions we clamp instead of call it
             invalid. But we try and track int or number to reject at
             parse time. If you do division it becomes a number. This
             is inconvenient for typed OM. We'd like any numbers to
             work out.
  TabAtkins: I think the distinction for int and number I wrote in is
             for convenience not a need. I propose if a prop only
             takes an int and calc in non-int we round to an int. We
             do this for animations already.
  TabAtkins: To match how animations of int are specified at 0.5 we
             round up.
  Rossen: Any other opinions
  Rossen: Or suggestions
  <tantek> that sounds like a reasonable proposal and way of re-using
           another approach of how we deal with this situation

  AmeliaBR: I believe someone said edge does this?
  TabAtkins: fremy said they do but they floor so he had a weak
             preference for that. I think match animations is better.
  AmeliaBR: Yes, doing actual rounding sounds more logical.
  Rossen: Wouldn't disagree. For matching with flooring or animations
          I'd also prefer animations.
  Rossen: So I would be fine with TabAtkins proposal.
  Rossen: Any other ideas or suggestions? If not we can resolve to
          accept current.
  Rossen: Objections?

  RESOLVED: Accept the proposal in #2337

Schedule Wrangling
==================

  Rossen: Snapshot 2018
  Rossen: dbaron Should we postpone?
  dbaron: I'm happy to postpone. May be better for F2F

  Rossen: Next is "Percentage sizing section is kind of vague"
  TabAtkins: Not 2 minutes
  TabAtkins: I would like people to ask for the 3rd Houdini issue as
             I'll edit that in?

CSS Typed OM
============

Trim CSSResourceValue and subclasses to opaque objects for this level,
    punt rest to level 2
----------------------------------------------------------------------
  github: https://github.com/w3c/css-houdini-drafts/issues/716

  TabAtkins: Quick summary
  TabAtkins: Hard to write a type hierarchy for JS that matches how
             URLs and images work in CSS. Per our previous Tokyo
             resolution in some properties we can't tell if it's an
             image or a mask reference until we fetched the resource.
             We can't even tell how to reflect it as a JS
  TabAtkins: Proposal is the URL always readifies as a CSS URL
             property. Image value is separate and used for other
             image things. Anything that needs to accept an image will
             accept both and if the URL is pointing to something else
             it's invalid. There's some plans for a level 2 in the
             issue. That's the basic issue.
  <plinss> +1
  TabAtkins: Simplify image handling for 2 classes and URLs are
             independent of any type.
  Rossen: Thanks. People who are interested please engage on that
          issue.

  Rossen: Reminder please look at spec rec steps and the proposed typo
          topics.
  Rossen: Thanks very much and we'll chat next week.
  Rossen: Bye!

Received on Thursday, 1 March 2018 00:56:40 UTC