Bug 246426

Summary: AX: List size is still announced by VoiceOver despite use of aria-setsize=-1
Product: WebKit Reporter: Todd Kloots <todd.kloots>
Component: AccessibilityAssignee: Andres Gonzalez <andresg_22>
Status: RESOLVED FIXED    
Severity: Normal CC: aboxhall, andresg_22, apinheiro, cfleizach, dmazzoni, ews-watchlist, jcraig, jdiggs, samuel_white, spanage, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: Safari 16   
Hardware: Mac (Intel)   
OS: macOS 12   
Attachments:
Description Flags
Video demo of the issue
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Patch
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Patch
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Patch none

Description Todd Kloots 2022-10-12 15:14:40 PDT 
Created attachment 462949 [details]
Video demo of the issue

What steps will reproduce the problem?
(1) Start VoiceOver
(2) Open https://codepen.io/toddlr/pen/abGXbzN
(3) Use tab to move focus to the first item in the list

What is the expected result?

VoiceOver should not announce the size of the list

What happens instead?

VoiceOver announces the size of the list on initial focus ("List with three items").
Comment 1 Radar WebKit Bug Importer 2022-10-12 15:15:02 PDT 
<rdar://problem/101099199>
Comment 2 Todd Kloots 2022-10-12 15:24:06 PDT 
For more context: all lists in Slack are virtualized. And so, with only the items scrolled into view actually rendered into the DOM VoiceOver reports the list size according to what is rendered into the DOM/scrolled into view. Therefore in 99.99% of cases in Slack the list size announced by VoiceOver will be inaccurate (“list of 5 items” when in fact it is a channel with loads and loads of messages) and could be confusing for users.

The ARIA spec indicates use of set-size="-1" when the size of the list is unknown. We've implemented this for all our virtualized lists in Slack, and yet VoiceOver is still announcing the list size.
Comment 3 Sommer Panage 2022-11-15 18:54:57 PST 
Confirming this still reproduces on 13.1 Beta (22C5044e)
Comment 4 Andres Gonzalez 2022-11-16 08:38:30 PST 
Created attachment 463557 [details]
Patch
Comment 5 Andres Gonzalez 2022-11-16 08:40:35 PST 
This is the WebKit portion of the fix, a VO change is also necessary.
Comment 6 Andres Gonzalez 2022-11-17 07:01:25 PST 
Created attachment 463580 [details]
Patch

Now works for ATSPI as well.
Comment 7 Andres Gonzalez 2022-11-18 14:18:48 PST 
Created attachment 463612 [details]
Patch
Comment 8 EWS 2022-11-18 16:19:26 PST 
Committed 256861@main (ca1977fd4ef6): <https://commits.webkit.org/256861@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 463612 [details].
Comment 9 Todd Kloots 2023-11-30 16:31:38 PST 
Verified fixed. Tested using Mac OS 14.1.1 in both Chrome (Version 119.0.6045.199) and Safari (Version 17.1 (19616.2.9.11.7).