Icons of application that reside in the system tray looks very strange:
As you can see: there is a gray square around the clipboard system tray icon. It's happens in many other apps in LMDE and in Mint 13+14. It seems that this is cinnamon problem (I use the latest one: 1.6.7)
It's not a critical bug but it's visually annoying
How can I solve this issue?