Usually it happens when I go into my notification fly-out and someone has “liked” one of my status updates.
I click it to see what was “liked” and get the dreaded bandaged thumb©. At first I thought Facebook might be deleting posts I’d put up, but it seems that it’s just a glitch. If I get the dreaded bandaged thumb©, but then go to my personal timeline, I’ll see that the post is still available, and the like that the person put on it shows up, I just can’t get to it from the notification flyout. It’s annoying, and should be fixed ASAP, but as long as I’m not being censored, so be it.