[winswitch] Using xpra with steam and amd64gpu on linux

[Christopher Faylor]

I recently had an off-the wall idea to use xpra with steam on my local
machine to achieve some degree of isolation from my normal X-Server.
I'd like my game (a windows game which works great under steam) to be
able to work in another workspace without interfering with my normal work.
Running steam in another workspace somewhat works but there is bleedover
with mouse events sometimes.  My mouse cursor gets changed and moved
randomly, which is pretty annoying.

xpra works really well with virtualgl so I was hoping that I could run
the game using that to get acceptable levels of performance but, while
demo things like "/usr/bin/glxsphere" work amazingly well, steam fails
to run anything due to this error:

vulkan: No DRI3 support detected - required for presentation
Note: you can probably enable DRI3 in your Xorg config
vulkan: No DRI3 support detected - required for presentation
Note: you can probably enable DRI3 in your Xorg config
Could not find both graphics and present queues

I've tried running xpra with a dummy driver via:

xpra start :100 --xvfb='Xorg -noreset +extension DRI3 +extension GLX +extension RANDR +extension RENDER -config xdummy.conf'

(xdummy.conf uses the dummy driver).

but that didn't help and I didn't really expect it to.

I don't think I'm going to be able to get beyond the DRI3 hurdle but I
thought I'd ask just in case there is a trick that would get this
working.

cgf