Alan Stearns | 16 Sep 22:52 2014

[CSSWG][css-line-grid] Updated WD of CSS Line Grid Level 1

The CSS WG has published an updated Working Draft of the CSS Line Grid
Module Level 1:

This module contains features for aligning content to a baseline grid.

This draft has reduced the feature set for the first level, and added
extensive examples of snapping lines to the baseline grid.

Significant changes are listed at:

Please send any comments to this mailing list, <www-style <at>>, and
please, prefix the subject line with


(as I did on this message).

For the CSS WG,


Tab Atkins Jr. | 16 Sep 20:56 2014

[css-grid] Doubts on worthiness of grid-auto-flow:stack

I just slightly reworked the auto-placement algorithm to define the
behaviors of the three placement algorithms separately, and I've come
to the conclusion that "stack" is a lot of difficulty for no benefit.

We originally created "stack" as an attempt to define a slightly
better version of the old "just put everything in 1/1" behavior.
Instead, it goes and finds the first *empty* slot, and puts everything
there; if you're not putting anything in 1/1, it'll have the same
behavior.  It's a little more complex than that to handle things with
a definite column position, though.

Having freshly written the algo, I just don't think it pulls its
weight.  It's still a terrible value, doing something you don't
actually want it to do.  It only exists to hopefully handle IE's
legacy content that depended on "auto-placing" things in 1/1, but it
might not even do that (if a page is currently positioning something
in 1/1 *and* depending on auto-placement to put more things there).  I
think we should just throw away "stack", add "none" with the behavior
that puts everything in 1/1 if its position is fully auto (and does a
simple "dense" packing for things that are auto in only one
dimension).  This would then prevent IE from having to make a
proprietary value for their old behavior, as we'd just match it.



Tab Atkins Jr. | 16 Sep 19:44 2014

[css-grid] auto-placement algorithm step 2 doesnt' respect sparse/dense/stack choice

In another thread, Manuel Casasnovas points out that step 2 of the
auto-placement algorithm (which processes items with a definite row
position but auto column position) doesn't vary its behavior based on
the algorithm specified in 'grid-auto-flow'.  Interestingly, it
actually does a "dense" packing, as it repeatedly looks for the
"earliest" spot in the row that the item will fit in.  (This makes
sense, as it's the easiest way to implement it; doing a sparse packing
would require more work, and wouldn't even maintain the ordering that
is the entire justification for sparse packing.)

Should we have this step pay attention to the algorithm, or leave it
as it is?  I'm inclined to leave it as it is.


Mark Watson | 16 Sep 17:41 2014

[mediaqueries] Media Source Extensions and device capabilities


Some time ago I raised on this list the idea that Media Queries should include some capabilities (such as native screen resolution, audio output channels) that might assist Javascript in selection of appropriate media to feed into the Media Source Extensions to the HTML Media Element [1]. For example the mediaMatch() function could be used to query device capabilities and to receive events in response to changes in device capabilities.

Since media queries are what are used declaratively for resource <-> capability matching on the HTML Media Element when using static resources, it seems natural to also use them for the Media Source Extension case.

At the time, the response was that resource selection should be performed by the UA, not the author. For adaptive streaming, this option has been on the table for a long time: various manifest formats exist which can describe available equivalent media streams (DASH, HLS, Smooth Streaming) and UA's *could* support these, giving complete control of the stream selection to the UA.

However, in practice, only one desktop UA has supported any such format, and it is a proprietary one (Safari and HLS). All desktop UAs are working on - and in some cases have deployed - the alternative Media Source Extensions model. That specification is close to CR. At least the two largest video sites in the US have adopted this approach and have large-scale deployed services.

Whilst this approach allows the site to adapt the streamed media to available bandwidth and certain device capabilities exposed by canPlayType and media queries, we are still missing the capability to adapt to display resolution and audio output capability.

These are optimizations and cannot be done perfectly. For example, a display may be HD but the video may be in a small window with less than SD resolution. Or a device may have a digital audio output connected, but it's connected to an amplifier that performs down-mixing to stereo.

Nevertheless, the optimizations which can be performed become quite valuable when considering UHD and high quality multi-channel audio. Optimizing for display capability not only saves bandwidth, but may avoid the need for downscaling, saving battery life.

In discussions in the html-media group, it's been suggested that this topic should be the subject of a general solution, not something specific to MSE.

Is there any interest in re-visiting this topic here ?


Mark Watson

Benjamin Poulain | 16 Sep 05:19 2014

[selectors] :nth-child(An+B of selector) with a pseudo element


Currently, :nth-child() does not restrict pseudo-elements like :not() does. Shouldn’t it have the
same restrictions?

For example:
    :nth-child(2n of ::after)
    :nth-child(2n+1 of ::first-letter)
do not make much sense.


Greg Whitworth | 16 Sep 01:45 2014

[CSS2.1] Position of absolute position box in relative box with text-align center

Hello all, I have the great pleasure of bringing another 2.1 interop issue to the list for discussion very
close to the last one regarding placement of absolute positioned boxes [1]. This one is interesting as
Chrome and FF place the box all the way to the left of the viewport while IE places it at the center. Based on
the 2.1 spec [3], I believe that IE is doing the correct thing in this case. Here is a fiddle of the interop
issue: and here is the markup with style inline for discussion:

<body style="text-align: center;">
	<div style="display: inline; position: relative;">
   		 <div id="parent" style="display: block; position: static;">
        			<div id="child" style=" display: block; padding: 5em; background-color: green; position:
absolute; ></div>

Since the wrapper box should be positioned at the center of the viewport due to text-align[2] the next
inline box should be starting its positioning there as well. Thoughts?




Bobby Tung | 13 Sep 15:49 2014

[css-ruby] Sample of tonal mark as ruby text attached to inline Bopomofo


Here is a sample for Bopomofo appears inline in vertical writing, and tonal mark as ruby text in printed
book. [1]

Ideally, it should be:

1, close to ruby base text as possible, and 
2, do not expand default line-height.

[2] is how it looked like in Safari.

It might be related to 3.5 Line Spacing.


WANDERER Digital Publishing Inc.
Bobby Tung
bobbytung <at>

Simon Pieters | 11 Sep 20:04 2014

[cssom-view][mediaqueries] vertical resolution when pixels are not square

RESOLVED: 'resolution' MQ uses the vertical resolution when pixels are not  

What should this do when the device is rotated? If it's supposed to switch  
to the new vertical, we haven't solved the problem that both aren't always  

If not, how do we define which is "vertical" for a rotatable device?

(Bug for cssom-view )


Simon Pieters
Opera Software

Chris Lilley | 11 Sep 18:02 2014

Sydney f2f dates


SVG WG just discussed and agreed with the proposed dates for the
Sydney f2f.

    Monday 9 - Tuesday 10 February, 2015. 
    Wednesday 11 February, 2015. 
    Thursday 12 - Saturday 14 February, 2015.


Best regards,
 Chris                          mailto:chris <at>

Simon Pieters | 11 Sep 16:49 2014

ACTION-545: Update CSSOM to throw SyntaxError on insertRule with above weirdness as argument


I noticed that I have an old action in tracker [1]. It's about insertRule  
with invalid stuff.

As far as I can tell this is well defined in the CSSOM spec now.

Empty string: step 2
"Otherwise, consume a qualified rule and let rule be the return value. If  
nothing was returned, return a syntax error."
...which then results in a SyntaxError in CSSOM.

Garbage after rule or more than one rule: step 4
"If the next input token is an <EOF-token>, return rule. Otherwise, return  
a syntax error."
...which then results in a SyntaxError in CSSOM.

What the return value is:
It returns /index/.



Simon Pieters
Opera Software

abhimanyu0003 | 10 Sep 08:19 2014

Easy CSS Icons Set

I propose that we have a set of full-CSS icons. Icon fonts can be used to add items like home, etc., but I think we will benefit if we have extremely simple rules for commonly used icons, like this:

<forwardicon/>, a self-closing tag, or something like
<icon class="forwardarrow"/>

Although adding a class defeats the purpose of embedded, fully CSS icons.

I think we should think about it. We can have stuff like:
  • Forward and Backward arrows in two variations (resembling > and -->)
  • Home icon
  • Mail ic on
  • Phone icon
  • Website icon
  • and others that are also supported in icon fonts.