Comment 4 for bug 1901648

I've found this bug too.
It fails on postinst script. I've checked it and I'm wondering why does it try to create zfs dataset when it already exists?

When I applied this patch, everything works OK:

--- /var/lib/dpkg/info/docker.io.postinst.orig 2020-11-08 23:21:14.561453080 +0100
+++ /var/lib/dpkg/info/docker.io.postinst 2020-11-08 23:21:25.104740749 +0100
@@ -31,7 +31,7 @@
    # /var with canmount off if doesn’t exist
    rpool="$(zfs mount | awk '$2=="/" {print $1}'| cut -d/ -f1)"

- if [ -n "$rpool" ]; then
+ if [ -z "$rpool" ]; then
     dockermnt="$(findmnt -n -o SOURCE /var/lib/docker || true)"

     # Create <currentpool>/var/lib/docker if doesn’t exist