Comment 44 for bug 1816497

Looks like it's working for me on 18.04 with upgraded libva since I see MojoVideoDecoder again. CPU usage seemed fair for a 2k video, details as follows:

CPU Usage
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~20%
Current / Optimal Res3840x1976@24 / 3840x1976@24
Codecsvp09.00.51.08.01.01.01.01.00 (313) / opus (251)
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LIBVA_MESSAGING_LEVEL=2 snap run chromium
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libva info: VA-API version 1.7.0
libva info: Trying to open /snap/chromium/1163/usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_7
libva info: va_openDriver() returns 0
[4410:4410:0520/195642.417532:ERROR:sandbox_linux.cc(374)] InitializeSandbox() called with multiple threads in process gpu-process.
libva info: VA-API version 1.7.0
libva info: Trying to open /snap/chromium/1163/usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_7
libva info: va_openDriver() returns 0
[4269:4269:0520/195642.435879:ERROR:browser_switcher_service.cc(238)] XXX Init()
[4269:4414:0520/195652.100085:ERROR:object_proxy.cc(632)] Failed to call method: org.freedesktop.PowerManagement.Inhibit.Inhibit: object_path= /org/freedesktop/PowerManagement/Inhibit: org.freedesktop.DBus.Error.AccessDenied: An AppArmor policy prevents this sender from sending this message to this recipient; type="method_call", sender=":1.559" (uid=1000 pid=4269 comm="/snap/chromium/1163/usr/lib/chromium-browser/chrom" label="snap.chromium.chromium (enforce)") interface="org.freedesktop.PowerManagement.Inhibit" member="Inhibit" error name="(unset)" requested_reply="0" destination="org.freedesktop.PowerManagement" (uid=1000 pid=1552 comm="xfce4-power-manager " label="unconfined")
[4269:4414:0520/195652.100117:ERROR:power_save_blocker_linux.cc(373)] No response to Inhibit() request!
[4269:4414:0520/195652.248926:ERROR:object_proxy.cc(632)] Failed to call method: org.freedesktop.PowerManagement.Inhibit.Inhibit: object_path= /org/freedesktop/PowerManagement/Inhibit: org.freedesktop.DBus.Error.AccessDenied: An AppArmor policy prevents this sender from sending this message to this recipient; type="method_call", sender=":1.564" (uid=1000 pid=4269 comm="/snap/chromium/1163/usr/lib/chromium-browser/chrom" label="snap.chromium.chromium (enforce)") interface="org.freedesktop.PowerManagement.Inhibit" member="Inhibit" error name="(unset)" requested_reply="0" destination="org.freedesktop.PowerManagement" (uid=1000 pid=1552 comm="xfce4-power-manager " label="unconfined")
[4269:4414:0520/195652.249213:ERROR:power_save_blocker_linux.cc(373)] No response to Inhibit() request!
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