[2/?] I went to the Software Store (GUI), hoping to see some updates: nope.
But then I went to the command line and did an apt-update/apt-upgrade, and 50+ packages were ready to be updated. That's irritating...
This obviously crushed my hopes that a Zorin OS user would never need to resort to the command line, you know?
So after a system update and another reboot, the graphics artifacting seems to have disappeared...