1725416 - [Pointer Event] button state inconsistency on touch devices

Status: VERIFIED FIXED

(Core :: DOM: UI Events & Focus Handling, defect, P3)

Description

[Ray]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0

Steps to reproduce:

Subscribe to the 'pointerdown' event:

window.addEventListener('pointerdown', (evt => console.info(evt.button, evt.buttons)))

Actual results:

On a touch enabled desktop (Windows), touching the screen results in:

0, 0

While a click gives:

0, 1

Expected results:

I expect 0, 1 in all cases. The current behaviour in FF 91 is inconsistent with:

• FF 90
• The documentation here: https://developer.mozilla.org/en-US/docs/Web/API/Pointer_events#determining_button_states

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::DOM: Events' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Comment 2

[Alin Ilea, Desktop QA]

Hi,

Here is the regression range, found using Lenovo Yoga(Windows 10) touchscreen device:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=1d7b099453e3b7863650db0d28065571fe320775&tochange=a8c952dcf42810501dbce59333fdd5867e9a1804

Comment 3

[Edgar Chen [:edgar]]

Kagami, would it be possible something caused by bug 1710317? Mind taking a look? Thanks!

Comment 4

[Kagami Rosylight [:saschanaz] (they/them)]

Oops, mozregression does point to bug1710317.

Comment 5

[Kagami Rosylight [:saschanaz] (they/them)]

Attachment: Bug 1725416 - Default to eNotPressed in WidgetTouchEvent r=edgar

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/217fff940bec
Default to eNotPressed in WidgetTouchEvent r=edgar

Comment 7

[Atila Butkovits]

Backed out for causing mochitest failures on test_getCoalescedEvents_touch.html.

Backout link: https://hg.mozilla.org/integration/autoland/rev/be3f13e32fe80a8554ab85caebd5f093b069c6f5

Push where failures appeared: https://treeherder.mozilla.org/jobs?repo=autoland&selectedTaskRun=amR3GiXtRU-RLGuEzikrFA.0&resultStatus=testfailed%2Cbusted%2Cexception%2Cretry%2Cusercancel&revision=2b0bb8247bb33438e393ef2c2f4e35dcdc60c093

Failure log: https://treeherder.mozilla.org/logviewer?job_id=349058700&repo=autoland&lineNumber=2941

Comment 8

[Pulsebot]

Backout by [e-mail]:
https://hg.mozilla.org/mozilla-central/rev/fe930f350465
Backed out changeset 217fff940bec for causing mochitest failures on test_getCoalescedEvents_touch.html. CLOSED TREE

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/d1fdf010c95e
Default to eNotPressed in WidgetTouchEvent r=edgar

Comment 10

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/d1fdf010c95e

Comment 11

[BugBot [:suhaib / :marco/ :calixte]]

The patch landed in nightly and beta is affected.
:saschanaz, is this bug important enough to require an uplift?
If not please set status_beta to wontfix.

For more information, please visit auto_nag documentation.

Comment 12

[Kagami Rosylight [:saschanaz] (they/them)]

No known real web compat issue so far, so marking as wontfix.

Hi reporter, if this issue is affecting your website or any web service you are using, please feel free to respond.

Comment 13

[Ray]

This affected a customer using our commercial product; we've responded with a workaround that seems to work for our specific needs, so the impact is manageable.

Comment 14

[Kagami Rosylight [:saschanaz] (they/them)]

Comment on attachment 9237025 [details]
Bug 1725416 - Default to eNotPressed in WidgetTouchEvent r=edgar

Beta/Release Uplift Approval Request

• User impact if declined: Touch behavior on some websites may be broken by this issue, e.g. as reported in comment #13.
• Is this code covered by automated tests?: Yes
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): This only restores the previous behavior
• String changes made/needed:

Comment 15

[Ryan VanderMeulen [:RyanVM]]

Comment on attachment 9237025 [details]
Bug 1725416 - Default to eNotPressed in WidgetTouchEvent r=edgar

Approved for 92.0b9 and 91.1esr.

Comment 16

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-beta/rev/e87bb5c16a2e

Comment 17

[Julien Cristau [:jcristau]]

https://hg.mozilla.org/releases/mozilla-esr91/rev/ecd759a45b3d

Comment 18

[Alin Ilea, Desktop QA]

Verified - Fixed in latest Nightly 93.0a1 (build id: 20210826213950), Beta 92.0b9 (build id: 20210826192006) and latest 91.1ESR (build id: 20210826130001) using Lenovo Yoga (Windows 10) touchscreen device. Touching the screen results in 0, 1.