1451478 - Broken slider buttons on ticketmaster.com

Status: RESOLVED INCOMPLETE

(Core :: Graphics: WebRender, defect, P1)

Description

[Darkspirit]

Debian Testing, KDE, Radeon RX480, 2560x1440

try builds from bug 1449562 comment 5:
> WR @ 3d541ccee469638603ec194da09227c991642c64
mozregression --repo try --launch 3b33947edef50c7f1cf9ee1d5f087067df57863e --pref gfx.webrender.all:true startup.homepage_welcome_url:"https://www1.ticketmaster.com/angels-in-america-ny-parts-1-new-york-new-york-04-05-2018/event/0300533BA19F3A85?artistid=2419828&majorcatid=10002&minorcatid=32&tm_link=artist_msg-0_0300533BA19F3A85"
Remove the drop-shadow from .modal-dialog to see the whole box: good

> WR @ 7ca4558f247ac02b9a49c0a9bf5d3972c451092f
mozregression --repo try --launch e9dc076b65fb82417dfe244c2516913c18f672b0 --pref gfx.webrender.all:true startup.homepage_welcome_url:"https://www1.ticketmaster.com/angels-in-america-ny-parts-1-new-york-new-york-04-05-2018/event/0300533BA19F3A85?artistid=2419828&majorcatid=10002&minorcatid=32&tm_link=artist_msg-0_0300533BA19F3A85"
bad

Regression range: https://github.com/servo/webrender/compare/3d541ccee469638603ec194da09227c991642c64...7ca4558f247ac02b9a49c0a9bf5d3972c451092f

Found and briefly discussed in: https://github.com/servo/webrender/pull/2588#issuecomment-378185499
> Thanks! Everything seems to be fixed, except for:
>  o bug 1447186: looks good (fixed bug), but the two ticket budget slider buttons have a broken shadow when zooming in (regression).
> 
> try build from https://github.com/servo/webrender/pull/2588#issuecomment-378130260:
> mozregression --repo try --launch cadd09929b8fc269d3af9795902726f4da897bde --pref gfx.webrender.all:true startup.homepage_welcome_url:"https://www1.ticketmaster.com/angels-in-america-ny-parts-1-new-york-new-york-04-05-2018/event/0300533BA19F3A85?artistid=2419828&majorcatid=10002&minorcatid=32&tm_link=artist_msg-0_0300533BA19F3A85"
> 
> -> Screencast: attachment 8964506 [details] (Debian Testing, KDE, Radeon RX480, 2560x1440)
> 
> This problem was still visible after three minutes without interaction.
> 
> Buttons and bug are gone if I remove the box shadow from them. The visual bug is larger than the element size (if I hover them with the devtools element picker).

Comment 1

[Darkspirit]

mozregression --repo try --launch e9dc076b65fb82417dfe244c2516913c18f672b0 --pref gfx.webrender.all:true startup.homepage_welcome_url:"https://www1.ticketmaster.com/angels-in-america-ny-parts-1-new-york-new-york-04-14-2018/event/0300533BA0893984?artistid=2419828"
* The box-shadow of a slider button is looking good when zooming in if I remove the drop-shadow from .modal-dialog before.
* If I just zoom in to 110% and remove the drop-shadow from .modal-dialog, I have something like a cached broken shadow only for that zoom level. All other zoom levels are fine then.

Comment 2

[Darkspirit]

Win10, Radeon RX480
ANGLE: The slider buttons are disappearing at other zoom levels than 100%.
non-ANGLE: Same as on Debian.

Comment 3

[Darkspirit]

try builds from bug 1453688:
> WR @ 53680df7f50bc15fcb010e5469386b19938bf9be
mozregression --repo try --launch 1209684335fab26349b6f90e3011fb0d48eebddd --pref gfx.webrender.all:true startup.homepage_welcome_url:'https://www1.ticketmaster.com/angels-in-america-ny-parts-1-new-york-new-york-06-30-2018/event/0300533BA0D039FA?artistid=2419828'
bad (permanently broken)

> WR @ 4be4420e3a432f0e4e80edbed15699ab54573982
mozregression --repo try --launch 891f0dc7bfe628f12291dca15fb9718e9153ecc5 --pref gfx.webrender.all:true startup.homepage_welcome_url:'https://www1.ticketmaster.com/angels-in-america-ny-parts-1-new-york-new-york-06-30-2018/event/0300533BA0D039FA?artistid=2419828'
better (only broken for a short moment when changing the zoom level)

Betterment range: https://github.com/servo/webrender/compare/53680df7f50bc15fcb010e5469386b19938bf9be...4be4420e3a432f0e4e80edbed15699ab54573982

= https://github.com/servo/webrender/pull/2656 
> Auto merge of #2656 - glennw:better-drop-shadow, r=kvark
literally ;)

Comment 4

[Darkspirit]

I think I could see this only with my Radeon RX480, but not with this GTX 1060. Have to set up my old PC again to check if this bug still exists.

Comment 5

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

darkspirit: Can you confirm whether or not you still see this? I don't believe I'm seeing any glitches at any zoom level, although if you are, a webcast of the issue would be appreciated :). The button does disappear when I take off the box-shadow, but that is expected behaviour (works the same without WebRender, and in Chrome).

Comment 6

[Darkspirit]

I am using the same Win10 with Radeon RX480 like before and only got some updates before I could use Windows: I am no longer able to reproduce this issue even with older Nightly versions (comment 2).