ISSUE-542: Text Alt Comp section on CSS generated content does not allow for proper CSS content fallback

TAC Generated Content

Text Alt Comp section on CSS generated content does not allow for proper CSS content fallback

AccNam AAM 1.2
Raised by:
James Craig
Opened on:

This section does not account for proper CSS generated content fallbacks.

<div style="content: url(icon.png), attr(data-fallback);" data-fallback="Bar">Foo</div>

According to the TAC, the accessible name should be "Foo" as an image replaced the text visually, but the modality-specific text replacement should be "Bar"… We should adjust the name computation to account for this, despite the fact that the modality-specific fallback does not yet work in any known UA.
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Also, the new 'alt' property in CSS4.

James Craig, 3 Feb 2014, 22:01:50

On Feb 5, 2014, at 1:49 PM, Tab Atkins Jr. wrote:

> On Mon, Feb 3, 2014 at 3:59 PM, James Craig wrote:
> Do you have an estimate for when the ‘alt’ property will be available
> in a draft of CSS4? I need to reference this from another spec. The
> section of the ARIA text alternative computation covering CSS generated
> content is woefully incomplete, and I’m hoping to fix it for ARIA 1.1.

It'll go into the Pseudo-Elements spec when someone picks that up again.

For now, just put a note into the ARIA stuff that it's expected that
CSS will define a way to explicitly provide alternative text for
generated content. Feel free to sketch it in the note if you'd like.

James Craig, 5 Feb 2014, 22:12:22

How universal is @data-fallback? If it is exclusive to HTML5, then this belongs in the HTML5 section of the TAC (i.e. not the core section).

Joseph Scheuhammer, 6 Oct 2014, 14:25:57

Move to Implementation guide. This has bigger impact on test tools and wcag authoring practices.

Richard Schwerdtfeger, 6 Oct 2014, 18:00:08

[MichaelC]: WCAG-ACTION-286 created for this

14 Oct 2014, 23:42:45

This requires coodination with the CSS Accessibility Task Force as it requires work by CSS and Host languages as well and is thus for not implemented in any browser today.

Richard Schwerdtfeger, 4 Apr 2017, 19:42:03


James Nurthen, 7 May 2018, 18:03:08

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