When I drag a file in Nautilus to drop it somewhere else (in a different folder but still within the same Nautilus window), Launcher launches with some "active" icons (the rest of 'em "disabled" / "grayed-out" for the time of that "revelation"). Which icons are "active" depends on the type of file being dragged, but Nautilus and the Rubbish Bin will always (?) be active.
I've noticed this happens in particular when horizontal scroll is visible in Nautilus (e.g., when you have long file names, etc) and when the file you drag is the one from the bottom of the list.
I've never found this "feature" useful, and would like to disable it. A quick check in CCSM didn't reveal the appropriate on-off switch.
What causes this behaviour?
How can I prevent Launcher from launching upon drag(-and-drop)?