I finally experienced my first "phantom" update notification in Ubuntu 9.04. In previous versions of the system, a little icon on the upper panel would notify me that updates were available. I could either click the icon and open the Update Manager, then do the update. But in this new system (I've been running 9.04 about a week), the icon is gone. At some interval that I don't understand, the Update Manager just opens, minimized. I brought the window up and did the updates.
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