1926982 - Overscroll effect resets with a jump when touching touchpad

Status: RESOLVED FIXED

(Core :: Panning and Zooming, defect, P2)

Description

[Markus Stange [:mstange]]

Steps to reproduce:

1. On macOS, with a touchpad, do a fast fling on a scrollable website.
2. During the rubberbanding animation, set two fingers on the touchpad and don't move them.

Expected results:
The overscroll animation should either pause or it should continue.

Actual results:
Overscroll snaps to zero instantly.

This is probably a regression from bug 1926141.

Comment 1

[BugBot [:suhaib / :marco]]

Set release status flags based on info from the regressing bug 1926141

:botond, since you are the author of the regressor, bug 1926141, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 2

[Markus Stange [:mstange]]

I'm also seeing strange behavior when putting the fingers on the touchpad in a subframe. When I pause at the start of a scroll, the movement of the scroll is delayed. I see this in the timeline of the profiler when having more threads visible than fit. The profiler has overscroll-behavior: none set on the html and body elements, which may be related.

Comment 3

[Donal Meehan [:dmeehan]]

The regressor Bug 1926141 was backed out of central

Comment 4

[Botond Ballo [:botond]]

I'm going to reopen this because it affects Linux as well. For Linux, the regressing bug is bug 1568722.

Comment 5

[Botond Ballo [:botond]]

Attachment: Bug 1926982 - Handle overscroll properly when handling hold gesture events. r=dlrobertson

Comment 6

[BugBot [:suhaib / :marco]]

Set release status flags based on info from the regressing bug 1568722

Comment 7

[Botond Ballo [:botond]]

(My bad, bug 1568722 first landed in 133, so 132 is unaffected.)

Comment 8

[Botond Ballo [:botond]]

(In reply to Markus Stange [:mstange] from comment #2)

I'm also seeing strange behavior when putting the fingers on the touchpad in a subframe. When I pause at the start of a scroll, the movement of the scroll is delayed. I see this in the timeline of the profiler when having more threads visible than fit. The profiler has overscroll-behavior: none set on the html and body elements, which may be related.

I've spun this off into bug 1929757.

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4b00477456e7
Handle overscroll properly when handling hold gesture events. r=dlrobertson

Comment 10

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/4b00477456e7

Comment 11

[Botond Ballo [:botond]]

Attachment: Bug 1926982 - Handle overscroll properly when handling hold gesture events. r=dlrobertson

Original Revision: https://phabricator.services.mozilla.com/D227749

Comment 12

[Phabricator Automation]

beta Uplift Approval Request

• User impact if declined: On a Linux system with touchpad hold gesture support, when a page is overscrolled, putting the fingers back down on the touchpad immediately cancels the overscroll animation
• Code covered by automated testing: yes
• Fix verified in Nightly: no
• Needs manual QE test: no
• Steps to reproduce for manual QE testing: N/A
• Risk associated with taking this patch: low
• Explanation of risk level: The code being modified is specific to overscroll. The impact is also expected to be limited to Linux systems on newer Wayland versions which have touchpad hold gesture support.
• String changes made/needed: none
• Is Android affected?: no

Comment 13

[Pulsebot]

https://hg.mozilla.org/releases/mozilla-beta/rev/ef9086df1ad4