She cleared the courtroom to have a birthday party for a kid because his father was going to jail for long time? I'm suppose to be angry about that??

So her "crime" is enjoying memes with her coworkers while not in the middle of a court case? She didn't rub it in the faces of any of the court participants.

Doctors, paramedics, police officers all engage in gallows humor. Just as just about every other set of professionals who enjoy some light hearted banter to break up the monotony of the day.