https://bugs.freedesktop.org/show_bug.cgi?id=83436
--- Comment #9 from Maciej gutigen@outlook.com --- Did an update today, performance decrease is still there, but fps drops are gone. I had no other apps running in the background, so I'm not sure what's up. However fps drops in TF2 are still a thing.
As for bisecting, I really have no skills to do that, I'm just a gamer with AMD card :/