Error notifcation in the status menu saying
An Error occured, please run Package Manager from the right-click menu or apt-get in terminal to see what's wrong. The error message was:'Unknown Error:''("The cache has no Package named 'steam'") This usually means that your installed packages unmet dependencies.
But there aren't any errors or warnings showing up when running apt-get on the command-line. And the notification won't go away.