Turris OS 6.0 is released

I’m running docker in a lxc container (followed guide here: Docker on Turris Omnia - #44 by ackstorm23)

after upgrading to 6.0 my lxc container won’t start with this error message:

lxc-start: ha: cgroups/cgfsng.c: cgfsng_mount: 1810 No such file or directory - Failed to create cgroup at_mnt 26()
lxc-start: ha: conf.c: lxc_mount_auto_mounts: 845 No such file or directory - Failed to mount "/sys/fs/cgroup"

Google says it is down to different versions of the cgroups subsystem? True or false? Anything I can do to fix it?