Snapshots don't work.

Unless I am doing something wrong, the snapshots feature doesn’t work. Whenever I click ‘Take Snapshot’ I hear the shutter sound, but nothing shows up in the snapshots window.

Is this a known bug?

It depends on whether the snapshots window is showing the snapshots for the document of which you are taking the snapshot. The chances are that you opened your snapshots window for one document, then took a snapshot of a different document. The snapshots window won’t change the document displayed until you select “Show Snaphots” for a different document.
Best,
Keith