1557875 - "Welcome to Office" headline and buttons missing from office.com

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect, P3)

Description

[Asif Youssuff]

Attachment: bad-Screenshot from 2019-06-07 20-02-16.png

Not entirely sure how to reproduce this (which preferences to enable, etc.)

1. visit office.com

What happens:

"Welcome to Office" headline and buttons missing from office.com. See screenshot.

Expected result:

Text and buttons.

8:20.60 INFO: No more inbound revisions, bisection finished.
8:20.60 INFO: Last good revision: b22a06518604e41f554a7f1dbd1d3f3bb1c70471
8:20.60 INFO: First bad revision: b4a7ea5163291c9918c6e09d44e0672a41bbaaaf
8:20.60 INFO: Pushlog:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=b22a06518604e41f554a7f1dbd1d3f3bb1c70471&tochange=b4a7ea5163291c9918c6e09d44e0672a41bbaaaf

Comment 1

[Asif Youssuff]

Attachment: good-Screenshot from 2019-06-07 20-05-27.png

Comment 2

[Asif Youssuff]

Attachment: wr-support

Comment 3

[Jeff Muizelaar [:jrmuizel]]

Can you reproduce the problem on Nightly? I don't see it on Nightly mac.

Comment 4

[Asif Youssuff]

Yeah, I am seeing it on nightly on Linux.

Oddly, I can't reproduce it if I copy prefs.js to a new profile, but it reliably reproduces with my current profile. Disabling all add-ons doesn't fix it either.

I used my current profile in mozregression and I got the regression range above. I can share my prefs.js if you would like, or I could try to strip private data out of my current profile and upload it here. Let me know what you would like.

Comment 5

[Asif Youssuff]

You can download my profile here - https://send.firefox.com/download/99c676569971436f/#CP7tbsDORTQby7QCvHSQAw

Comment 6

[Jessie [:jbonisteel] pls NI]

I don't see this problem on Windows

Comment 7

[Andrew Osmond [:aosmond] (he/him)]

I am able to reproduce on both Linux and Windows by changing the zoom.

Comment 8

[Glenn Watson [:gw]]

I seem to recall that the office.com page has some "interesting" ways of using scrolling with transforms, I've seen regressions on this page before.

I'll assign this to me and see if I can reproduce if I have time this week, but at currently traveling for the all-hands.

Comment 9

[Liz Henry (:lizzard)]

Too late for 68 but we could still take a patch for 69.

Comment 10

[Glenn Watson [:gw]]

I did some investigation on this today. It's a little tricky to reproduce - it depends on screen resolution and zoom level, but it does happen.

I can reproduce on my laptop on a 4k screen with maximized window and any zoom level < 100%. Setting zoom to 90% is a reliably way to see the bug on my configuration.

The clipper logic for plane splitting gets invoked at https://searchfox.org/mozilla-central/rev/da14c413ef663eb1ba246799e94a240f81c42488/gfx/wr/webrender/src/picture.rs#2564 appears to fail in this case.

The transform is axis-aligned - if I hard code the logic here to instead invoke the simple logic (for the identity scale case) the bug disappears.

I wonder if this is some kind of float accuracy issue in the clipper? Dzmitry, any ideas on the cause of this?

Comment 11

[Dzmitry Malyshau [:kvark]]

No need for need-info, since it's assigned on me now :)

Comment 12

[Liz Henry (:lizzard)]

Is this still something you might work on? Thanks!

Comment 13

[Dzmitry Malyshau [:kvark]]

Sorry, I lost this issue. Will work on it.

Comment 14

[Dzmitry Malyshau [:kvark]]

I'm no longer able to reproduce it on 70.0a1 (2019-08-13)
There was a plane-splitting/clipping fix in https://phabricator.services.mozilla.com/D41390 that has been uplifted to Beta (see bug 1572197).
Asif, are you able to reproduce this now?

Comment 15

[Asif Youssuff]

This was fixed.

10:37.86 INFO: No more inbound revisions, bisection finished.
10:37.86 INFO: First good revision: 65d774a64533b15a6baee649364f5331a9241a0f
10:37.86 INFO: Last bad revision: 4784b03e2ffde547fb0bba7f65d30b39e2c918a9
10:37.86 INFO: Pushlog:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=4784b03e2ffde547fb0bba7f65d30b39e2c918a9&tochange=65d774a64533b15a6baee649364f5331a9241a0f