1616078 - ::marker contents appear duplicated in accessibility tree

Status: RESOLVED FIXED

(Core :: Disability Access APIs, defect, P2)

Description

[Oriol Brufau [:Oriol]]

Load

<style>
::marker { content: 'foo' counter(bar) }
</style>
<ol><li>text</li></ol>

Inspect the <li> in the accessibility tree.

Actual

▼ listitem      "foo0 foo 0 text"
    statictext  "foo0"
    statictext  "foo"
    statictext  "0"
    statictext  "text"

Expected: I guess something like

▼ listitem      "foo0 text"
    statictext  "foo0"
    statictext  "text"

or

▼ listitem      "foo 0 text"
    statictext  "foo0"
    statictext  "text"

or

▼ listitem      "foo0 text"
    statictext  "foo"
    statictext  "0"
    statictext  "text"

or

▼ listitem      "foo 0 text"
    statictext  "foo"
    statictext  "0"
    statictext  "text"

or similar.

Comment 1

[Marco Zehe (:MarcoZ)]

This is also confirmed with NVDA. Moving this from the developer tools to the platform APIs component. Jamie, seems like our list item code is grabbing text too much too often. Question is how this is visually represented, what the result should be.

Comment 2

[James Teh [:Jamie]]

The danger of me investigating an issue is that I end up patching it...

Comment 3

[James Teh [:Jamie]]

Attachment: Bug 1616078: Don't use HTMLListBulletAccessible for CSS ::marker content.

::marker content gets handled like text from any other CSS pseudo-class.
Therefore, using HTMLListBulletAccessible ends up duplicating the content already exposed in the a11y tree.
Now, we only use HTMLListBulletAccessible for nsBulletFrames instead of all marker frames.

As part of this, remove nsContainerFrame::GetSpokenMarkerContent, since we no longer need it to retrieve ::marker content.
The bulk of its other work was done by nsBulletFrame::GetSpokenContent, which we now call directly.
It also handled producing a default bullet character for list-style-image, but it makes sense for this to live in the a11y code.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/d1704ff79f8f
Don't use HTMLListBulletAccessible for CSS ::marker content. r=eeejay,emilio,MarcoZ

Comment 5

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/d1704ff79f8f