1273010 - Blocky and slow rendering on Firefox Android Nightly - filter: drop-shadow()

Status: ASSIGNED

(Core :: Graphics, defect, P3)

Description

[Karl Dubost💡 :karlcow]

This is a spin-off of the Web Compatibility Report 
https://webcompat.com/issues/1983

Steps to Reproduce.

1. With Firefox Android Nightly 49.0a1 (2016-05-11) (but happened previously too)
2. (Set Request Desktop Site - Just to activate the feature which was disabled for Firefox on this site by the site owner)
3. Go to https://inkbunny.net/submissionview.php?id=942282&page=31
4. Once the page has loaded, click another graphics icons
5. On the new page scroll down and up quickly, the rendering is very blocky or delayed.

This is not happening on Chrome for Android.


The site owner singled out a property
.shadowedimage { filter: drop-shadow(0 0 2px #343434) }

When remove the site is smooth again.

In the comment, he says:
https://webcompat.com/issues/1983#issuecomment-172095597

> I managed to get Mobile 44.0b9 loaded up in the 
> x86 emulator, and it locks up for periods of 
> fifteen seconds with full CPU usage there, too; 
> the vast majority of the time appeared to be spent 
> within DisplayList::Draw :5610 and gfxUtils::DrawPixelSnapped

Comment 1

[Karl Dubost💡 :karlcow]

I wonder if Markus has an idea about this.

Comment 2

[Markus Stange [:mstange]]

I can reproduce this and will take a look.

Comment 3

[mc.prince.0203]

I still have the same issue on Firefox 64.0.2 on Android.

This is the minimum reproduction (please view on Android and scroll down): https://j4lp366v45.codesandbox.io/
and source code: https://codesandbox.io/s/j4lp366v45

Also, this is my website with drop-shadow()s. The animation works smoothly on Chrome on Android, but is not rendered correctly on Firefox on Android: https://ciffelia.com/

Comment 4

[Firefox Bug Husbandry Bot]

Migrating Webcompat whiteboard priorities to project flags. See bug 1547409.

Comment 5

[Firefox Bug Husbandry Bot]

See bug 1547409. Migrating whiteboard priority tags to program flags.