For some reason, some icons (Twitter for Mac) among them, are not showing up when I click the application folder in the dock. COMPLETELY not showing, as if they don't exist, not even with the white place holder and "anti-" sign (circle with a diagonal line through it) placeholder as sometimes happens with OS X. Doesn't matter if I show list, or grid, or automatic, there is no icon for Twitter for Mac at all, nothing between Tweetdeck and Typinator. However, when I go to the finder and click on the Applications folder, it is there. In between Tweetdeck and Typinator as it should be. The applications can be launched as well, so they were installed properly. Any reason for the disconnect? Why it would show up in one place but not the other? I always thought the dock folder was supposed to be an exact mirror. Does anyone know how to fix?