I just tried to open Spotify's Mac app through the OS X LaunchPad, and when I clicked on the icon, the Mac app icon remains stuck on my screen.
I've attached some screenshots to show you. I don't know how to get it down. No matter what I do to the screen, the icon is always stuck "on top" of it.
How do I make this go away? If you're curious, Spotify opened on the second attempt. The first attempt it just got stuck.