Mac App Store shows update count but section is collapsed/empty My updates badge shows 6 (also in the  menu), but the section in the updates tab seems to be collapsed (top separator line is thicker, like two lines) and not showing the available apps. I'm currently running macOS 10.12.1 (Mac App Store 2.2) and first noticed this problem today. The other tabs are behaving normally and this badge has changed from 5 to 6 updates today. I've tried restarting my computer, but the problem persists. Any ideas for fixing this?
Had the same problem. Solved by going to the "Purchased" tab on the App Store, looking for software that needed to be updated (xCode, iMovie, GarageBand, Numbers, Pages, Keynote) and clicking there on "Update". I also started downloading a new App. Some 15 secs later they appeared on the "Updates" tab as well. Including a "Software Update" that contains a new iTunes, what I was looking for actually.