Created attachment 589746 [details]
xpra 2.2.2-r1 build log
xpra-2.2.x fails to compile with ffmpeg 4. The only version of xpra that successfully compiles with the stable ffmpeg 4 is xpra 2.4.3, but it is not currently marked stable.
Created attachment 589748 [details]
xpra-2.2.6-r2 build log
Unfortunately, xpra 2.4.3 seems to be broken (see bug #694806).
And upstream has 2.5.3 now, so they won't support it at all...