I'm running Kubuntu 16.04 LTS in VirtualBox. Logging in works fine. However, as soon as I click anywhere on the panel, it not only disappears, but it also seems to take the Plasma Desktop Shell along with it. (i.e., apps I launch won't appear on the screen, etc.) I'm not sure if this is a problem on hard metal or not, so I'm going to drop it here. If this has been solved already, feel free to link me to where the solution is, please.
Blessings!
Blessings!