Open Bug 1475412 Opened 2 years ago Updated 9 days ago

WebRender Mac regression: Garbled content after opening 2nd window.


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

63 Branch





(Reporter: hen000.c.young, Unassigned)


(Blocks 2 open bugs)


(Keywords: nightly-community, regression, Whiteboard: [gfx-noted])


(3 files)

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:60.0) Gecko/20100101 Firefox/60.0
Build ID: 20100101

Steps to reproduce:

1) Set 'gfx.webrender.enabled' to 'true'.
2) Browse the web.
3) Open another browser window

Actual results:

When the 2nd browser window is open all content in both windows as well as the browsers chrome becomes garbled. See attached screenshot. This behaviour did not occur on old versions when WebRender was enabled.

Expected results:

The webpage should have displayed as normal.

Link to page the screenshot is of:
Component: Untriaged → Graphics: WebRender
OS: Unspecified → Mac OS X
Product: Firefox → Core
Hardware: Unspecified → x86_64
Could you please open about:support, click on the "Copy text to clipboard" button, paste it into a text file and upload it here (Attach File)? If you can get that information after things broke, it might be even more useful. Thanks!
You said this didn't happen on old versions - can you use mozregression to identify the changes that introduced this behaviour?

For example:
mozregression --good 2018-06-01 --bad 2018-07-13 --pref gfx.webrender.all:true
Attached file about-support.txt
Going back to look at old versions of Nightly I can't actually find a version that doesn't have the same bug. This is making me think the bug might be related to the release of macOS 10.13.6 as that was around the time when I started noticing the bug, although I haven't had issues in any other applications.
So ran into the bug in a new situation, I had only 1 firefox window open which normally works fine with webrender and then I opened a RAW photo in macOS's Preview app and the Firefox window got corrupted. So other applications can trigger the corruption in Firefox but are fine themselves.
See Also: → 1476273
FWIW I did a check for macOS updates on my older MacBook Air running 10.13.5, and there were no updates available. Assuming you got the 10.13.6 update via the usual mechanism, Apple might have pulled the update due to this or other issues. At any rate we'll have to wait and see if the issue persists when they do release 10.13.6 (again).
i think i updated to 10.13.6 yesterday, i'll look at this when i'm home later today
Priority: -- → P2
Whiteboard: [gfx-noted]
I got the 10.13.6 update today, but haven't seen this issue so far.
Attached is a screenshot from an Apple service document somebody shared online on a thread I found with other people also experiencing graphics issues since updating that details some graphical issues in recent versions of macOS.
Blocks: wr-mac
No longer blocks: stage-wr-trains
See Also: → 1491196
See Also: → 1438958
See Also: → 1553578
Priority: P2 → P3
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