User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:80.0) Gecko/20100101 Firefox/80.0

Steps to reproduce:

I am using FF with WebRender enabled, with its Wayland bacend. I enabled the following config options:

media.ffmpeg.dmabuf-textures.enabled
media.ffmpeg.vaapi-drm-display.enabled
media.ffmpeg.vaapi.enabled

and disabled:

media.ffvpx.enabled

I then used the 'enhanced-h264ify' add-on to selectively use vp9 and h264 codecs (because that is what my hardware supports):

VA-API version: 1.8 (libva 2.8.0)
Driver version: Intel i965 driver for Intel(R) Kaby Lake - 2.4.1
VAProfileH264Main                 : VAEntrypointVLD
VAProfileH264High                 : VAEntrypointVLD
VAProfileH264MultiviewHigh : VAEntrypointVLD
VAProfileH264StereoHigh      : VAEntrypointVLD
VAProfileVP9Profile0              : VAEntrypointVLD
VAProfileVP9Profile2              : VAEntrypointVLD

And then played videos on YouTube.

Actual results:

When using VP9, it runs for about a minute and then stops and shows the following message:

An error occurred. Please try again later. (Playback ID: ...) 

When using H264 (avc1), it stutters at ~10 second intervals, and makes watching the video impossible.

Expected results:

It should have plays videos of both codecs properly.

Can you check if the issue still takes place on Nightly (currently Fx 81 soon to be 82)?

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

The product::component has been changed since the backlog priority was decided, so we're resetting it.
For more information, please visit auto_nag documentation.

Thanks, bot. I missed that component had not been set, resetting priority.

VAAPI is definitely broken in 80, the first VAAPI on X11 release. It's fixed in Beta 81 and Nightly 82. (It was left broken for Wayland.)