Review for Update Notifier by John Callahan
Rated 5 out of 5 stars
@CrispyRoll: You can prevent individual extensions from updating in pref.js. Type about:config in the address bar. You'll need to create a new boolean value in the form of extensions.{GUID}.update.enabled.
I use extensions.{582195F5-92E7-40a0-A127-DB71295901D7}.update.enabled to keep GMail Manager from updating.
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