Several years ago some of the upper elementary girls made a private facebook page where they were talking badly about other girls in the class. Eventually, as it always does, it got out and many kids and their parents were hurt. I think it still hasn't been forgotten.
I think you raise a very important point when you write that you doubt that the incident has been forgotten. Videos and other texts caution that what we post remains in cyberspace forever, mostly to caution people to avoid posting images or information that could cost them a job, but it is important to note that bullying hurts for a long time.
You are correct in saying, "never forgotten." A similar situation has happened at the school I sub for many years ago and it is still brought up every now and then. Mainly as a learning tool for the next set of students at the beginning of the year. We ALL need to remind ourselves and others that we are "modeling behavior for others."