I've seen a picture that shows Joyce DeWitt holding up a production slate in the kitchen area of the apartment and smiling. It appears to be somewhere between seasons 4 and 6 due to Joyce having the short hair look. Anyone know the episode it's from?

It looks like the pic was taken after episode 0425 wrapped, which was "Jack's Graduation." It aired May 6, 1980. That was the final episode of season 4.