Resizing a lvm-thin container

e2fsck -fy /dev/pve/vm-423-disk-0
(autoshrink to smallest possible)
resize2fs -M /dev/pve/vm-423-disk-0
lvreduce -L 10G /dev/pve/vm-423-disk-0
(fill fs to 10G)
resize2fs /dev/pve/vm-423-disk-0


[edit /etc/pve/lxc/423.conf]
rootfs: local-lvm:vm-423-disk-0,size=10G