A pair of bugs that I noted and made an account specifically to report, though not sure if you guys are already aware. The first I noted is that 'Fell Empowerment' buff from a Potion of Dire Empowerment doesn't seem to be running out. I can't really tell you how to replicate it, since by the time I noticed it, I was eyeball deep in a monster zoo and not complaining that a buff wasn't wearing off. Other buffs I had at the time were Syzygy, Raidiant Aura, and Bad Weapon, along with food and drink, though I'm not sure if this information helps at all. The second happened as I closed the game with a few enemies and a pet Friendly Wyrmling on screen. When I relogged, none of the enemies attacked the wyrmling, though it was attacking all of the enemies it could catch up to. When I tried to re-summon it to 'fix' it, I got a second wyrmling instead.
If you eat a Fell Truffle, followed by a Potion of Dire Empowerment, you'll get a permanent buff of some sort. The second issue is a known pet bug. You can have many pets this way, because the game doesn't remember your "old" pet when you reload a game. It also sets the old pet's AI to the old stupid monster AI, thus the non-tanking behavior.