Literally blocks playback on videos when enabled, telling you that you have to subscribe to a patron for "premium" features, otherwise you have to disable it.
I did one better: I'd straight up just removed this waste of storage space of an extension and am now giving it a 1-star review, zero stars if I could. Yes, I'm aware that extensions like this cost money to run and maintain, but putting up a "free" extension only to block it behind a paywall only drives people away towards competitors. Unbelievable.