Linux only: The latest version of Ubuntu pops the Update Manager dialog window onto the screen every time there are updates to install—very irritating if you are in the middle of something.
Instead of automatically launching the dialog window, previous versions of Ubuntu showed the Update Manager icon in the tray when there were updates to install, and the Make Tech Easier blog runs down the process of disabling that annoying automatic popup dialog for good. You can simply open gconf-editor, browse down to Apps -> Update Notifier, and uncheck the auto_launch option to force Update Manager to behave.
Readers will note that you should always keep your system patched and up-to-date at all times, and this tweak doesn't disable Update Manager in any way—it simply removes the automatic popup, since having an in-your-face dialog window is unnecessary.
How to Remove the Annoying Update Manager Popup [Make Tech Easier]