Bug of firefox 98. From Firefox - ArchWiki
Note: As of Firefox 98, VA-API is blocked by RDD sandbox, but can be used by setting the environment variable
MOZ_DISABLE_RDD_SANDBOX=1, although this is less secure. [11]
I personally don’t suggest to disable sandbox as this is a very serious security risk and even more so if you are using a “web browser”. From Firefox - ArchWiki
As a last resort, the content process sandbox can be disabled. However, this is a serious security risk and disables protection against attackers. It is recommended to leave the sandbox settings as default [18].
Here’s what you can do for now:
- Disable HW on firefox tiil the issue is fixed (Don’t downgrade firefox!)
- Switch to Chromium as I have done.