I have experienced similar symptoms with F15, bit I realized later that actually I just had a very large number of battery status notifications, and clicking many dozens of times cleared them out.

This message is a notice that Fedora 15 is now at end of life. Fedora
has stopped maintaining and issuing updates for Fedora 15. It is
Fedora's policy to close all bug reports from releases that are no
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of '15' have been closed as WONTFIX.

(Please note: Our normal process is to give advanced warning of this
occurring, but we forgot to do that. A thousand apologies.)

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