Firefox 75 came out not long ago and I am try to get the VAAPI hardware video acceleration working but I have ran into a weird issue I am wondering if anyone else has encountered. I have all the correct settings and it reports to be using wayland, webgl and all that good stuff but I get the following when I try to load a H264 video and the tab just crashes.
[me@laptop ~]$ MOZ_ENABLE_WAYLAND=1 MOZ_LOG=“PlatformDecoderodule:5” firefox
Sandbox: seccomp sandbox violation: pid 6019, tid 6247, syscall 64, args 1140872792 1 1974 140652209324032 0 0.
Sandbox: seccomp sandbox violation: pid 6019, tid 6247, syscall 64, args 1140872792 1 438 140652209324032 0 0.
###!!! [Parent][MessageChannel] Error: (msgtype=0x59001C,name=PHttpChannel::Msg_DeleteSelf) Channel error: cannot send/recv
However if I run with the environmental variable set to disable this sandboxing (MOZ_DISABLE_CONTENT_SANDBOX=1) it runs fine and offloads the video to my GPU, Anyone know why this is or how to fix it? maybe I should try the flatpak instead
Note after some more research setting security.sandbox.content.level to 3 provides no crash but some strange visual glitches in video playback and switching it to 2 fixes the issue