Strangely, my application indicators -- the ones for Mail, Sound, and Network Manager -- occasionally stop responding to left clicks. Or right clicks. Any clicks at all. Fortunately, I can always scrub over from the right-most power icon.
closed as off topic by Stefano Palazzo♦ Jul 3 '11 at 12:37
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That is a known bug, and only happens on unity if you are running an application in the system tray. However, you don't provide much more in terms of detail, so you will have to tell me if this is a different situation.