Opera has had this feature for years and features more playback controls than FF. It seems many features start on Opera then get "invented" in other browsers afterwards.
You're right that it has been in Opera for years. Specifically it was introduced back in 2016. But Maxthon had it first, introducing it in 2010. Snaps or webpage screenshoting as well (2010), which was later put in Opera (2017) and recently on Firefox.
