- Blue glitches appear randomly when interacting with Gnome Shell.
Graphic artifacts in Ubuntu 11.10,12.04 Unity, Fedora 16,17,18,19 Virtual Machines running in GNOME 3 desktop environment and in Linux Mint Cinnamon after installing Parallels Tools.
Your Mac is equipped with AMD Radeon 6xxx or Intel 5000 video cards.
NOTE: To find out what video card your Mac is equipped with, please click on Apple Logo -> About This Mac -> More Info... -> check Graphics string
This is a known issue. Parallels Desktop Maintenance team is currently working on its resolution.