1603026 - Randomly missing letters in web content and chrome UI text with WebRender on macOS

Status: RESOLVED FIXED

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

Description

[Chris Peterson [:cpeterson]]

Attachment: screenshot.jpg

[Tracking Requested - why for this release]:

This is a regression in 73 Nightly (build 2019-12-10) from the fix for Adreno bug 1598380.

With gfx.webrender.all enabled on macOS, I see random letters missing from both web content and chrome UI text. See the attached screenshot.

I bisected this regression to this pushlog:

https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=05327537443557099272b63ade89fe36f0ad05e1&tochange=3f9482614123972f6fcd8b6a1d99dc8db8cb6c07

Comment 1

[Chris Peterson [:cpeterson]]

Attachment: about:support

Here is my about:support for my 2015 MacBook Pro running macOS 10.15.1.

Comment 2

[Chris Peterson [:cpeterson]]

I don't see this problem on my Windows laptop.

Comment 3

[Jamie Nicol [:jnicol]]

Thanks for the report! This doesn't look good. I'd expect it not to affect windows, as it does not use PBOs. But the fact I cannot reproduce on Linux, Android, or my 2013 13" MBP, leads me to believe this is a driver bug of sorts :(.

Does this happen on all sites? Does it happen immediately, or after scrolling around a little?

Would you be able to set gfx.webrender.debug.texture-cache=true, restart, and take a screenshot as soon as it reproduces?

Thanks!

Comment 4

[Timothy Nikkel (:tnikkel)]

There are 3 other bugs filed within the past few hours for what looks like this same issue: bug 1603033 bug 1603018 bug 1602981
So this is probably pretty widespread.

Comment 8

[Jamie Nicol [:jnicol]]

This appears to affect AMD macbooks with Catalina only (though that's probably the most common configuration!). I have gotten my hands on one of those so can now investigate further.

Comment 10

[Chris Peterson [:cpeterson]]

(In reply to Jamie Nicol [:jnicol] from comment #3)

Does this happen on all sites? Does it happen immediately, or after scrolling around a little?

This happens immediately on all sites and even chrome UI text (like about:newtab and the bookmarks toolbar).

Would you be able to set gfx.webrender.debug.texture-cache=true, restart, and take a screenshot as soon as it reproduces?

(In reply to Jamie Nicol [:jnicol] from comment #8)

This appears to affect AMD macbooks with Catalina only (though that's probably the most common configuration!). I have gotten my hands on one of those so can now investigate further.

Since you now have an AMD ok to test, I assume you don't need me to test gfx.webrender.debug.texture-cache=true on my MBP. Let me know if you still would like me to test.

Comment 11

[Jamie Nicol [:jnicol]]

Yep, no need. Thanks!

Comment 12

[:Atoll]

(In reply to Jamie Nicol [:jnicol] from comment #8)

This appears to affect AMD macbooks with Catalina only (though that's probably the most common configuration!). I have gotten my hands on one of those so can now investigate further.

I forgot to add that, sorry (in my duped-to-here) - iMac 21.5” Retina (2017) which is essential a MacBook glued to the back of a screen, and does have AMD.

Comment 14

[Jamie Nicol [:jnicol]]

This was fixed by backing out bug 1598380

Comment 15

[Cristian Fogel [:cfogel]]

Dropping the qe+ since we cannot reproduce the issue with our devices.