http://docs.pilotmoon.com/article/5-popclip-faq Why does the Edit menu flash sometimes when I use PopClip? The edit menu flashing is a result of the way PopClip works, and this can't be "fixed". It happens when PopClip asks the application you are to copy the selected text to the clipboard briefly, so PopClip can see it. OS X flashes the Edit menu title when the Copy command is invoked.