For some time I've noticed some of the older Facebook albums I'd created from either iPhoto or Aperture showed with generic icons when displayed in Aperture's Facebook view. After a recent Aperture update to 3.51 I decided to investigate; I right clicked on the icons and navigated to the albums in Facebook.
Which had no images in them. It sounds like this bug, documented back in 2010 (as I write this I think Discussions has gone offline):
... I was pleased that the Aperture 3.1 update fixed a lot of bugs related to Facebook, however it seems to have introduced a new bug. When I started Aperture after the update, it brought in all my Facebook albums (about 10 of them), however one of the albums was empty. I went on Facebook to see that this album still existed but was also empty. It seems that Aperture deleted the contents since there were obviously pictures in it before the update. I created a new album in Aperture and uploaded it successfully to Facebook. The photos stayed intact until the next time I opened Aperture after which it deleted all the photos again. I repeated this 5 times before giving up. It only affected the one previous album (seemingly random) and any new albums I try to create. I've since disconnected Aperture from Facebook and only upload through Safari. Anyone seen something similar?...
I saw some similar comments in Apple Discussions, but not much elsewhere. Looking back at my albums the most last empty album was some time in summer 2011. So perhaps the bug, which might have belonged to Apple or Facebook or both, was fixed after that.
The photos are still in Aperture -- though I had a stomach ache moment when I thought they weren't. So this appears to be a synchronization bug, of the sort that have plagued me for years decades. Synchronization is tough, and Apple has failed at it more than once.
I could recreate the albums by exporting images from Aperture and uploading via Safari, but for now I'll leave them be.
If you used Aperture or iPhoto @2010-2011 with Facebook you should take a look at your albums.