1495962 - Floating table header moves and snaps back when scrolling down (should'nt move at all)

Status: VERIFIED FIXED

(Core :: Graphics: WebRender, defect, P2)

Description

[Mayank Bansal]

Attachment: bandicam 2018-10-03 08-09-10-769.mp4

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:64.0) Gecko/20100101 Firefox/64.0

Steps to reproduce:

1. Enable WR
2. Go to https://www.androidcentral.com/poco-f1-vs-oneplus-6
3.  There is a comparison table in the middle of the page
4. Scroll down from the table


Actual results:

the "floating" table header moves down, and then snaps back continously

From the looks of it, this is a APZC+WR bug


Expected results:

not so.

Comment 1

[Mayank Bansal]

ni? ,as this looks like a APZ issue

Comment 2

[Mayank Bansal]

I am scrolling using the mousepad on a laptop

Comment 3

[Darkspirit]

A regression date would have to be before 2018-01-15.

Comment 4

[Darkspirit]

It's broken since it was implemented:
> Emilio Cobos Álvarez — Bug 975644: Enable position sticky in table parts. r=bz

Comment 5

[Mayank Bansal]

well, this reproduces only with WR for me.

Comment 6

[Kartikaya Gupta (email:[e-mail])]

Thanks. I can look at this when I'm done my current set of bugs. Leaving unassigned for now in case somebody else wants to do it first.

Comment 7

[Liz Henry (:lizzard) (relman/hg->git project)]

Marking fix-optional for 64. We could still take a patch for 65, and if it's verified and doesn't seem risky, could still take fixes for 64 as well.

Comment 8

[Kartikaya Gupta (email:[e-mail])]

Attachment: Minimal test case

Minimal testcase to repro. Basically, both the <tr> and the <th> are sticky-positioned, so presumably we end up applying the sticky offset twice, or something like that. With async scrolling the header ends up moving against the scroll instead of staying in place.

Comment 9

[Kartikaya Gupta (email:[e-mail])]

https://treeherder.mozilla.org/#/jobs?repo=try&group_state=expanded&revision=9248c1317a942a91216c4cfde0bc58f71a71f85b

Comment 10

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1495962 - Add reftests for nested sticky-positioning r?kvark

Comment 11

[Kartikaya Gupta (email:[e-mail])]

https://treeherder.mozilla.org/#/jobs?repo=try&group_state=expanded&revision=f40f9ac5dfe05ebb6793b3d81ac4fcae3d68d49e

Comment 12

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/90db69624281
Add reftests for nested sticky-positioning r=kvark

Comment 13

[Eliza Balazs [:ebalazs_]]

Backed out changeset 90db69624281 (Bug 1495962) for reftest failures in reftests/position-sticky/nested-sticky-2.html DONTBUILD

Failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=217619196&repo=autoland&lineNumber=2201
https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=217619215&repo=autoland&lineNumber=15068

Push with failures: https://treeherder.mozilla.org/#/jobs?repo=autoland&resultStatus=testfailed%2Cbusted%2Cexception%2Cusercancel%2Crunnable&revision=1fbdcb9480daf162357da72ee263c41165bcac27&selectedJob=217623217&searchStr=windows%2C7%2Creftest

Backout: https://treeherder.mozilla.org/#/jobs?repo=autoland&resultStatus=testfailed%2Cbusted%2Cexception%2Cusercancel%2Crunnable&revision=7b860a9f49a97c6c67b6f4cae452c1630ac17079

Comment 14

[Kartikaya Gupta (email:[e-mail])]

Looks like it needs a little fuzz on win7

Comment 15

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/e023011bce62
Add reftests for nested sticky-positioning r=kvark

Comment 16

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/276e3568f74f
Follow-up to fix overeager fuzzing. r=me

Comment 17

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/05d1120d5b91
Loosen fuzz range for win 7 reftest jobs. r=me

Comment 18

[Bogdan Tara[:bogdan_tara | bogdant]]

https://hg.mozilla.org/mozilla-central/rev/e023011bce62
https://hg.mozilla.org/mozilla-central/rev/276e3568f74f
https://hg.mozilla.org/mozilla-central/rev/05d1120d5b91

Comment 19

[Kartikaya Gupta (email:[e-mail])]

WR only, not severe/common enough to uplift, I would say.

Comment 20

[Vlad Lucaci, Thunderbird QA (:vlucaci)]

Hello,

Confirming this issue as verified fixed on Windows 10x64 with 66.0b14 and 67.0a1 (2019-03-08)on an nVidia GTX 1060 GPU.