Facebook messages not appearing in notification centre
I'm on OSX 10.8.5, 27" imac. The notification centre used to show Facebook messages, but now it doesn't show me anything from Facebook. Reminders and emails appear, but they don't remain in the centre, even though I have ticked the 'Show 20 recent items' box in settings. Also Facebook is on Alert with most recent 20 items ticked, but notification centre remains empty. It was working a few months ago then stopped. Any suggestions?
OS X Mountain Lion (10.8.5), Facebook integration