i encoded one 10bit/444 video, it seems to work fine...
but of course better testing will be very useful)
it seems i can't attach repacked sources due to very slow internet /
just put content of x264 git cloned folder into x264-snapshot-20210615 and tar it, and then xz it too....
$ mkdir x264-snapshot-20210615-master
cp -ar x264/* x264-snapshot-20210615-master/
tar -cf x264-snapshot-20210615.tar x264-snapshot-20210615-master
xz - 9 x264-snapshot-20210615-master.tar