1399480 - Painting issue

Status: RESOLVED FIXED

(Core :: Web Painting, defect)

Description

[Tarek Ziadé (:tarek)]

[Tracking Requested - why for this release]:

When I scroll a long page that's fully loaded, I get a white screen that can last up to 10 seconds on my macbook air with servo enabled. 

https://www.w3.org/TR/html5/single-page.html

Looks like a bad painting issue

Comment 1

[David Burns :automatedtester]

I have the same issue. About:support

Application Basics
------------------

Name: Firefox
Version: 57.0a1
Build ID: 20170913100125
Update Channel: nightly
User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:57.0) Gecko/20100101 Firefox/57.0
OS: Darwin 16.7.0
Multiprocess Windows: 1/1 (Enabled by default)
Web Content Processes: 4/4
Stylo: false (disabled by user)
Google Key: Found
Mozilla Location Service Key: Found
Safe Mode: false

Crash Reports for the Last 3 Days
---------------------------------

Report ID: bp-c2c5c001-66e9-41d1-8a55-9f9a80170912
Submitted: 1 day ago

All Crash Reports

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Graphics
--------

Features
Compositing: OpenGL
Asynchronous Pan/Zoom: wheel input enabled; scrollbar drag enabled; keyboard enabled; autoscroll enabled
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WebGL 1 Driver Renderer: Intel Inc. -- Intel(R) Iris(TM) Graphics 6100
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GPU #1
Active: Yes
Vendor ID: 0x8086
Device ID: 0x162b

Diagnostics
AzureCanvasAccelerated: 1
AzureCanvasBackend: skia
AzureContentBackend: skia
AzureFallbackCanvasBackend: none
TileHeight: 1024
TileWidth: 1024
Decision Log
WEBRENDER:
opt-in by default: WebRender is an opt-in feature




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Places Database
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Sandbox
-------

Content Process Sandbox Level: 3
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Comment 2

[David Burns :automatedtester]

I have tried this with Servo turned off (as seen in comment 2) and the painting and caching of the painting looks a lot better on larger documents.

Comment 3

[Stuart Philp :sphilp]

I see this with and without stylo, and is also reproducible on Facebook if you scroll the feed to get a lot of content loaded and then try to scroll back. I compared to Chrome as well, which feels like it limits scroll speed (using mbp trackpad) but you don't see any blanking either.

Comment 4

[Jet Villegas (inactive)]

I see this too. Recent regression--build from 9/10 didn't have it. Matt: can you help track this down? Thx.

Comment 5

[Julien Cristau [:jcristau]]

per comment 4.

Comment 6

[Matt Woodrow (:mattwoodrow)]

I'm not able to reproduce this locally.

Can someone that can repro please run mozregression [1] for this testcase?



[1] http://mozilla.github.io/mozregression/quickstart.html

Comment 7

[Jet Villegas (inactive)]

(In reply to Jet Villegas (:jet) from comment #4)
> I see this too. Recent regression--build from 9/10 didn't have it. 

I'm not seeing this in today's build. I do get the typical checkerboarding we get with APZ on fast-scrolling the HTML5 spec, but it's not the same as before (checkerboarding + scroll position not updating.)

Comment 8

[Jet Villegas (inactive)]

(In reply to Tarek Ziadé (:tarek) from comment #0)
> [Tracking Requested - why for this release]:
> 
> When I scroll a long page that's fully loaded, I get a white screen that can
> last up to 10 seconds on my macbook air with servo enabled. 
> 
> https://www.w3.org/TR/html5/single-page.html
> 
> Looks like a bad painting issue

Does this still occur for you? That is, do you still see 10 seconds of blank screen after you stop scrolling?

Comment 9

[Tarek Ziadé (:tarek)]

No it works like a charm now for me !

Stuart can you try ?

Comment 10

[Tarek Ziadé (:tarek)]

and David

Comment 11

[Stuart Philp :sphilp]

I'm still seeing the checkerboarding when scrolling quickly too, but it pops back once you stop. There's a bit of lag on the scroll position when you get going quickly, it hitches a bit, which isn't a nice visual (scroll position hitching + checkerboarding at the same time). 

0 checkerboarding would be nice, but I suspect that's oos here ;)

Comment 12

[David Burns :automatedtester]

This appears to work for me now.

Comment 13

[Tarek Ziadé (:tarek)]

Marking this as fixed- Stuart feel free to reopen if you feel this is still a problem for 57