1730856 - Mousewheel/touchpad scrolling stopped working on fixed background images with body height 100vh

Status: VERIFIED FIXED

(Core :: Web Painting, defect, P3)

Description

[Kestrel]

STR:

1. Visit https://mcibb.github.io/mcibb/.
2. Make sure the window width is larger than 1024px.
3. Move the cursor over the background image.
4. Try to scroll the page with the mousewheel or touchpad.

Mousewheel/touchpad scrolling doesn't work when initiated over the background image, only over text. Other page scrolling methods work normally, including keyboard, scrollbar and autoscroll. Works on Chrome.

Disabling background-attachment: fixed from the images or removing height: 100vh or overflow-x: hidden from the body allows mousewheel scrolling to work.

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=576f61f7bb0f92b5e73dea66232912df2dd7d7c0&tochange=08c8d6946406b113c3725c999479c9dd67d2abef

Regressed by Bug 1689207

Comment 1

[Robert Mader [:rmader]]

Hm, that patch likely just enabled HW-WR by default. Could you try if older version are also affected when you pass in --pref gfx.x11-gfx.webrender.all:true to mozregression?

And mind sharing your about:support?

Comment 2

[Darkspirit]

Can reproduce.

Comment 3

[Darkspirit]

Debian Testing, Gnome Xwayland, Intel, 2560x1440
mozregression --good 2020-09-10 --bad 2021-09-10 --pref gfx.webrender.all:true -a https://mcibb.github.io/mcibb/

7:37.59 INFO: Last good revision: cc4889143d653957d83a6e2ca9ea89691d39b435
7:37.59 INFO: First bad revision: f72030ee528939167d88804b61faa200246e037c
7:37.59 INFO: Pushlog:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=cc4889143d653957d83a6e2ca9ea89691d39b435&tochange=f72030ee528939167d88804b61faa200246e037c

f72030ee528939167d88804b61faa200246e037c Miko Mynttinen — Bug 1534549 - Part 4: Shrink nsDisplayCompositorHitTestInfo r=mstange
1907d855cb60b8e1eccd92513441a9a0f4aa5e27 Miko Mynttinen — Bug 1534549 - Part 3: Add tests r=mstange
fe81233c13cf45a57b6f422c5d05ac2a50e22071 Miko Mynttinen — Bug 1534549 - Part 2: Allow all display items to carry hit testing information r=mstange
56d9644b5a41b253a398157dd812d4cf7b12e30a Miko Mynttinen — Bug 1534549 - Part 1: Remove old FLB hit test info optimization r=mstange

Basic was not affected:
mozregression --repo autoland --launch f72030ee528939167d88804b61faa200246e037c --pref gfx.webrender.force-disabled:true -a https://mcibb.github.io/mcibb/

Comment 4

[Darkspirit]

The other WR-only scrolling bug is bug 1695822.

Comment 5

[Miko Mynttinen]

Can reproduce on Linux. Looking into this.

Comment 6

[Miko Mynttinen]

Changing severity to S2 because of regression.

Comment 7

[Miko Mynttinen]

Attachment: scroll.html

Simplified testcase.

Comment 8

[Miko Mynttinen]

Attachment: Bug 1730856 - Part 1: Use the correct scroll target for fixed backgrounds. r=mstange

Comment 9

[Miko Mynttinen]

Attachment: Bug 1730856 - Part 2: Add test. r=mstange

Depends on D127120

Comment 10

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/8216b43fec63
Part 1: Use the correct scroll target for fixed backgrounds. r=mstange
https://hg.mozilla.org/integration/autoland/rev/23f67b8ae851
Part 2: Add test. r=mstange

Comment 11

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/8216b43fec63
https://hg.mozilla.org/mozilla-central/rev/23f67b8ae851

Comment 12

[Ciprian Georgiu, Desktop QA]

Reproduced this issue with the test case from comment 7, on an affected Nightly build, running macOS 11.

The issue is verified as fixed on latest Beta 94.0b6, under macOS 11, Win 11, and Ubuntu 18.04 x64.