Being bored, I decided to see how the Kubuntu 20.04 Plasma desktop runs on top of ZFS.

Unfortunately, the Kubuntu 20.04 installer does not offer ZFS as a root filesystem.

So, I decided to re-install virt-manager and install Ubuntu 20.04 as a VM using ZFS as the rfs and then issue
sudo apt install kubuntu-desktop
to install KDE and its standard applications. Then I'm going to uninstall KMail, KPIM and baloo.

Then start playing around.

EDIT:
Thanks to Terence for the following link:
https://openzfs.github.io/openzfs-do...0on%20ZFS.html
Caveat from the article:
If you want a single-disk, unencrypted, desktop install, use the installer. It is far easier and faster than doing everything by hand.