Open Radar

 
Summary:
  Usually when the system is set to "require password (in my case Immediately) after sleep or screen saver begins" in System Preferences, it's not possible to interact with the desktop as there is the black backdrop behind the username/password entry screen. However, I somehow managed to time exiting the screensaver at just the right moment, where it didn't do the black backdrop correctly.

  I was able to record a short video (no audio) with my iPhone when it occurred that can be viewed here: http://s.jasonrm.net/r7j85q

Steps to Reproduce:
  Unable to reproduce… The best that I can recall as to what lead to the odd state was that I was sitting in front of my MacBook Pro while working on another laptop nearby. The screensaver started on the MacBook Pro and so, out of habit, I quickly pressed a key to prevent it from going into the screensaver and locking, but instead of just returning to the desktop, it ended up in that odd state.

Expected Results:
  Black backdrop and no ability to interact with anything except the username/password unlock dialog box.

Actual Results:
  Able to interact with the desktop and windows in a limited fashion. I was able to open & close Finder windows and scroll in a Safari window. I'm not sure what all would be possible, for example could I have dragged a file from the desktop to a USB drive?

Regression:
  Have only seen this once on a MacBook Pro 5,1 with Mac OS X 10.6.4 (believe it was build 10F569)