I updated both my 2009 MacBook Pro and my late 2012 iMac. The Macbook seems fine. Runs great for an 'old' machine. However the iMac has an issue - the share sheet in Safari is blank with a grey out 'No Service' text in place of any destinations. Is there somewhere i should be checking to turn it on? I didn't do anything on my Macbook and that works fine. Is it possible to trash the Safari app and download it again (separate from the whole OS) to fix this?