Exp awarded glitch.
This glitch is really only a visual issue and not much else, but sometimes when exp earned is displayed you will go back a few levels and be awarded a ridiculous amount such as 10 million exp. I think overall it doesn’t change the amount of exp you are actually supposed to earn though. Here is an example below, at this point half of the exp had been awarded and I was 6 levels below my actual level according to the exp bar.
When this happens though, it happens to everyone on the server.