Tried installing with ZFS, but two failures during format, I think.

[Andrew Cochrane]

Trying to install with zfs.
First attempt had drive mounted.
Second attempt with unmounted drive failed to format, maybe.
Third attempt failed after sending me time timezone selection. Then collected error report and brought me to the webpage.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ubiquity 20.04.15.10
ProcVersionSignature: Ubuntu 5.8.0-43.49~20.04.1-generic 5.8.18
Uname: Linux 5.8.0-43-generic x86_64
NonfreeKernelModules: wl zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: amd64
CasperMD5CheckResult: pass
CasperVersion: 1.445.1
CurrentDesktop: ubuntu:GNOME
Date: Tue Mar 23 10:09:25 2021
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed initrd=/casper/initrd quiet splash --- maybe-ubiquity
LiveMediaBuild: Ubuntu 20.04.2.0 LTS "Focal Fossa" - Release amd64 (20210209.1)
ProcEnviron:
 LANGUAGE=en_US.UTF-8
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 LC_NUMERIC=C.UTF-8
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)

[Andrew Cochrane (acochrane)]

I tried to install with ZFS again after rebooting.
It worked fine when making the first attempt when the target drive was not mounted.