[css3-ui] PFWG comments on CSS Basic User Interface Module Level 3

Below are comments from the Protocols and Formats WG on CSS3 UI, draft
of 17 January 2012 http://www.w3.org/TR/2012/WD-css3-ui-20120117/. These
comments have not all been vetted by the PFWG, but we are mindful of the
extended deadline you gave us, which we appreciate and acknowledge we
are slightly late to that. Thus not all comments may rise to the status
of WG-to-WG comments but we appreciate you taking a look, and can give
input on relative priority in follow-up discussion if needed. PFWG
discussion allowing me to send these comments in their current form is
archived at http://www.w3.org/2005/02/minutes#item08 (Member link).
Thank you for your deadline extension.

4.1.1 :active Details
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#active]
Does this only apply during click, or also during keypress (enter/space)
on focused elements?
 
4.1.4 :valid and :invalid
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#pseudo-validity]
What is the difference between “lacks data validity semantics” and “has
no constraints”? An example would be good here.
 
4.1.7 :read-only and read-write
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#pseudo-ro-rw]
What is the difference between these state and text input fields
attribute "disabled"?

4.2 Fragments
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#pseudo-elements]
This could really help accessibility by allowing authors to style real
form elements to look as desired, rather than creating their own
controls with similar functions. Can you add some examples of how this
would work with HTML?
 
5.1 'content' Property Addition
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#content-property-addition]
Can the icon property be used to replace regular icons with high
contrast versions? If so, please provide an example of that.

The content property in CSS 2.1 is problematic for accessibility, and is
the subject of a WCAG failure.
http://www.w3.org/TR/WCAG20-TECHS/failures.html#F87. Are there any plans
to address accessibility issues with content? This may be out of scope
for this review.
 
6.1 'box-sizing' Property
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#box-sizing]
Border-box looks promising for layouts stretch without tables. Probably
need a WCAG technique for this, and a failure for making fake tables for
actually tabular data.
 
7. Outline Properties
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#outline-properties]
Outline-width=none is an accessibility problem, as it can be used to
remove the focus rectangle from elements. Can we suggest that it be
deprecated?  Or not allowed on focusable elements?
 
8 Resizing & Overflow
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#resizing-amp-overflow]
The resize property is good. Users can resize elements that have clipped
their contents so that the content can be viewed. This sort of clipping
is a common bug when users resize the font in browsers or operating
systems, and having a mechanism to adjust is a good thing. Zooming has
made this bug less common, but it still occurs with some OS settings.
Any chance this could default to ‘both’ so that users can resize things
when the author hasn’t thought of it?
 
8.2 Overflow Ellipsis: the 'text-overflow' property
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#text-overflow]
This is nice for improving understandability. Seems like it could make
things less confusing for users with cognitive impairments.
 
9.1.1 'cursor' Property
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#cursor]
How is the cursor type exposed to users who are not using a mouse or
cannot see? It would be useful to have an example that sets cursor type
based on aria role/state/property combinations.

Jaws has a feature “Indicate Cursor shape changes”, but that’s
proprietary (and we are not sure if all shape variants are indicated).
We need more typed common behavior here.
 
9.2.1 Sequential Navigation Order: the ‘nav-index’ property
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#nav-index]
This looks promising, but needs some examples of how it addresses the
problems in tabindex
1) An example of how to use this with absolute positioning to address
tab order problems.
2) An example of how to use this with flexbox to fix tab order problems.
3) How this interacts with screen-reader reading order.
4) An example of how to use with aria-flowto, aria-owns, etc
5) Description of what happens when both tabindex and navindex are present.
 
9.2.2 Directional Focus Navigation: the ‘nav-up’, ‘nav-right’,
‘nav-down’, ‘nav-left’ properties
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#nav-dir]
Really nice, and looks very promising. Would also like to see some
description of how it interacts with ARIA.
 
9.2.3 Input Method Editor: the ‘ime-mode’ property
[http://www.w3.org/TR/2012/WD-css3-ui-20120117/#input-method-editor]
CSS property controls: active and inactive:
Interesting feature. However, since these states are left to the users
to activate, visually impaired users may not be aware of it, because a
lot of screen readers do not look into the style of the page. We suggest
deprecating it as WAI-ARIA markup is better meant for them.


-- 

Michael Cooper
Web Accessibility Specialist
World Wide Web Consortium, Web Accessibility Initiative
E-mail cooper@w3.org <mailto:cooper@w3.org>
Information Page <http://www.w3.org/People/cooper/>