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Bug 1760359

Summary: [HiDPI] Firefox on wayland doesn't play videos smoothly
Product: [Fedora] Fedora Reporter: Juan Orti <jorti>
Component: firefoxAssignee: Martin Stransky <stransky>
Status: CLOSED EOL QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 31CC: 0xalen+redhat, anto.trande, gecko-bugs-nobody, jan.public, jhorak, john.j5live, kengert, pjasicek, rhughes, rstrode, sandmann, stransky
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2020-11-24 18:45:45 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On:    
Bug Blocks: 1054334    
Description Flags
about:support with layers.acceleration.force-enabled=false
Firefox on Wayland about:support on new profile none

Description Juan Orti 2019-10-10 11:34:04 UTC
Description of problem:
Youtube videos don't play smoothly in Firefox on Wayland on F31. They lag and are not in sync with audio. If I use firefox-x11, the playback is very smooth.

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:
1. Play 1080p video in Firefox on Wayland
2. Compare with Firefox on X11

Actual results:
Video playback lags and not smooth

Expected results:
Smooth playback

Additional info:
Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz
00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 620 (rev 07)

$ vainfo 
libva info: VA-API version 1.6.0
libva info: va_getDriverName() returns 0
libva info: Trying to open /usr/lib64/dri/
libva info: Found init function __vaDriverInit_1_6
libva info: va_openDriver() returns 0
vainfo: VA-API version: 1.6 (libva 2.6.0.pre1)
vainfo: Driver version: Intel i965 driver for Intel(R) Kaby Lake - 2.3.0
vainfo: Supported profile and entrypoints
      VAProfileMPEG2Simple            :	VAEntrypointVLD
      VAProfileMPEG2Simple            :	VAEntrypointEncSlice
      VAProfileMPEG2Main              :	VAEntrypointVLD
      VAProfileMPEG2Main              :	VAEntrypointEncSlice
      VAProfileH264ConstrainedBaseline:	VAEntrypointVLD
      VAProfileH264ConstrainedBaseline:	VAEntrypointEncSlice
      VAProfileH264ConstrainedBaseline:	VAEntrypointEncSliceLP
      VAProfileH264Main               :	VAEntrypointVLD
      VAProfileH264Main               :	VAEntrypointEncSlice
      VAProfileH264Main               :	VAEntrypointEncSliceLP
      VAProfileH264High               :	VAEntrypointVLD
      VAProfileH264High               :	VAEntrypointEncSlice
      VAProfileH264High               :	VAEntrypointEncSliceLP
      VAProfileH264MultiviewHigh      :	VAEntrypointVLD
      VAProfileH264MultiviewHigh      :	VAEntrypointEncSlice
      VAProfileH264StereoHigh         :	VAEntrypointVLD
      VAProfileH264StereoHigh         :	VAEntrypointEncSlice
      VAProfileVC1Simple              :	VAEntrypointVLD
      VAProfileVC1Main                :	VAEntrypointVLD
      VAProfileVC1Advanced            :	VAEntrypointVLD
      VAProfileNone                   :	VAEntrypointVideoProc
      VAProfileJPEGBaseline           :	VAEntrypointVLD
      VAProfileJPEGBaseline           :	VAEntrypointEncPicture
      VAProfileVP8Version0_3          :	VAEntrypointVLD
      VAProfileVP8Version0_3          :	VAEntrypointEncSlice
      VAProfileHEVCMain               :	VAEntrypointVLD
      VAProfileHEVCMain               :	VAEntrypointEncSlice
      VAProfileHEVCMain10             :	VAEntrypointVLD
      VAProfileHEVCMain10             :	VAEntrypointEncSlice
      VAProfileVP9Profile0            :	VAEntrypointVLD
      VAProfileVP9Profile0            :	VAEntrypointEncSlice
      VAProfileVP9Profile2            :	VAEntrypointVLD

Comment 1 Martin Stransky 2019-10-10 12:11:09 UTC
Can you try to enable HW acceleration, set layers.acceleration.force-enabled to true at about:config and restart the browser.

Also can you attach your about:support?

Comment 2 Juan Orti 2019-10-10 12:50:21 UTC
layers.acceleration.force-enabled=true is definitely an improvement and now for example the lips and synced with the audio, but I still get small "jumps" in the video. The playback is smoother in X11.

Comment 3 Juan Orti 2019-10-10 12:51:18 UTC
Created attachment 1624348 [details]
about:support with layers.acceleration.force-enabled=false

Comment 4 Martin Stransky 2019-10-10 14:24:41 UTC
Can you try standard trouble shooting steps [1], especially:

1) Create a fresh new profile with disabled addons
2) Test Mozilla binaries with Wayland



Comment 5 Juan Orti 2019-10-14 06:39:29 UTC
Created attachment 1625483 [details]
Firefox on Wayland about:support on new profile

The same behaviour with new profile and addons disabled.

Comment 6 Martin Stransky 2019-10-14 12:12:31 UTC
Can you also try latest Mozilla binaries to check it's not Fedora specific issue [1]? Thanks.


Comment 7 Martin Stransky 2019-10-14 19:46:56 UTC
I wonder if that's - do you have a monitor which does not use 60Hz frequency?

Comment 8 Juan Orti 2019-10-15 07:33:21 UTC
Ok, it looks related to the resolution. I do the tests with Youtube 1080p60 videos. This is my setup:

$ xrandr
XWAYLAND0 connected 3072x1728+1920+0 (normal left inverted right x axis y axis) 600mm x 340mm
   3072x1728     59.94*+
XWAYLAND2 connected 1920x1080+0+772 (normal left inverted right x axis y axis) 340mm x 190mm
   1920x1080     59.96*+

Laptop display: 1920x1080 resolution. Video playback is very smooth, even to full screen.
Monitor: 4K resolution 60 Hz, with 125% scaling. The playback is only smooth if the Youtube video is in the default size (although subjectively not as smooth as in the laptop display). In bigger sizes like cinema mode or fullscreen, the video lags.

In X11, the playback is always smooth on both monitors at any size.

I've also tested the Mozilla binaries version 69.0.3 with a clean profile and the results have been the same.

Comment 9 Juan Orti 2019-10-21 13:42:35 UTC
It's the factional scaling of Gnome Shell. With a 100% o 200% scaling this problem doesn't happen.

Comment 10 Ben Cotton 2020-11-03 17:04:03 UTC
This message is a reminder that Fedora 31 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora 31 on 2020-11-24.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
Fedora 'version' of '31'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version.

Thank you for reporting this issue and we are sorry that we were not 
able to fix it before Fedora 31 is end of life. If you would still like 
to see this bug fixed and are able to reproduce it against a later version 
of Fedora, you are encouraged  change the 'version' to a later Fedora 
version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events. Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

Comment 11 Ben Cotton 2020-11-24 18:45:45 UTC
Fedora 31 changed to end-of-life (EOL) status on 2020-11-24. Fedora 31 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen this bug against that version. If you
are unable to reopen this bug, please file a new report against the
current release. If you experience problems, please add a comment to this

Thank you for reporting this bug and we are sorry it could not be fixed.