User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:75.0) Gecko/20100101 Firefox/75.0

Steps to reproduce:

I have enabled the webrender support for Linux and things are running very fast (I would say htm5 test x12 faster).

Actual results:

While I am watching a video or just browsing I could notice flashing horizontal white stripes randomly on the browser area. I am not completely sure but it seems this starts after I resume the laptop from s3 state (suspend-to-ram). Stripes are usually less 1 cm and appear and disappear very fast and appear randomly.

Expected results:

No horizontal white stripes should appear.

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

About support has several "Updating unknown shared surface", might that be the cause?

That message seems from come from [1] - maybe Andrew or Sotaro know what that means?

[1] https://searchfox.org/mozilla-central/source/gfx/layers/wr/WebRenderBridgeParent.cpp#919

It seems message is not related to this issue. Initially I do not see any of the white stripes but I do see GLX error messages. I think those messages appear when I close some tab but the system is still drawing something. Of course all of this is subjective (from my point of view).

Additionally when I watch video the issue is more prominent and again those white stripes are not just in the video area but also outside.

(In reply to Glenn Watson [:gw] from comment #4)

That message seems from come from [1] - maybe Andrew or Sotaro know what that means?

[1] https://searchfox.org/mozilla-central/source/gfx/layers/wr/WebRenderBridgeParent.cpp#919

It is shared image related code.

• https://searchfox.org/mozilla-central/rev/158bac3df3a1890da55bdb6ffdaf9a7ffc0bfb0a/gfx/layers/ipc/SharedSurfacesChild.cpp#130
• https://searchfox.org/mozilla-central/rev/158bac3df3a1890da55bdb6ffdaf9a7ffc0bfb0a/gfx/layers/ipc/SharedSurfacesChild.cpp#560

I wonder if it is a similar problem to Bug 1469496 and Bug 1484782.

Because this bug's Severity has not been changed from the default since it was filed, and it's Priority is P3 (Backlog,) indicating it has been triaged, the bug's Severity is being updated to S3 (normal.)

Some updates - I have upgraded to Firefox 76.0.1 and it seems better. I see the problem rarely but it still exists. There is also one strange thing - when I clicked on help->about (so I can get prices version) the pop window staid transparent inside. After I closed it and open again content inside the windows was visible - have not see this issues so far.

Hi Guys,

After further investigation I do not believe issue is on Firefox side. I see the same issue with other apps like Skype. With further investigation turning off vsync in KDE composer fix the issue (half way throught).

Thanks for the help.