1068291 - $ELEMENT:focus{position:relative;} should not trigger creation and destruction of accessible objects

Status: RESOLVED FIXED

(Firefox :: Disability Access, defect)

Description

[Joanmarie Diggs]

Attachment: children-destroyed.html

Steps to reproduce:
1. Open the attached test case in Firefox
2. Launch DOM inspector and watch mutation events and text events
3. Tab and Shift Tab between the two focusable elements in the test case

Expected results: No event spewage in DOM inspector

Actual results: Each time the focused element is changed:
1. text selection changed (from the link)
2. hide (from the link)
3. text removed (from the parent div)
4. show (from the link)
5. text inserted (from the parent div)
6. reorder (from the parent div)

From the perspective of ATs, the above combined with the associated accessible object:children-changed events means that the user moves to an object which is immediately destroyed as a result of having moved to that object. It plays havoc on Orca's ability to present content, thus it would be super if you stop destroying and recreating these objects. :)

Comment 1

[Joanmarie Diggs]

Attachment: Real-world test case: sshd.org.zip

FWIW: I'm attaching the content that led me to discover this issue. A large number of the focusable elements get destroyed and recreated upon receiving focus. :-/

Comment 2

[Trevor Saunders (:tbsaunde)]

Your probably going to hate me for saying it, but but we can't really do that, at least without doing a whole lot of work.

When the layout of something changes we need to recreate accessibles too, because of things like :focus{after: "foo"} which will create a new accessible for the anon text node for "foo".  So maybe we could rework rework tree updating stuff to try and do more inplace instead of destroy and rebuild, but we might have to have some way to know layout changes that can change the accessible tree from changes that can't.


Y

Comment 3

[Trevor Saunders (:tbsaunde)]

That said the new accessible should be focused, and maybe there is a focus event fired on it.

Comment 4

[alexander :surkov (:asurkov)]

(In reply to Joanmarie Diggs from comment #0)
> It plays havoc on Orca's ability to present content, thus it would
> be super if you stop destroying and recreating these objects. :)

It doesn't look like something that can be fixed soon. Focus should be refired for recreated accessible, that can be used for workaround I think.

Comment 5

[James Teh [:Jamie]]

Confirmed that we no longer re-create these accessibles now that bug 686400 is fixed.