...is the one where the labels in your inventory are mixed up.
So you click on a branch and end up fueling the kiln with "bone arrow" and you click on the bucket and end up filling a "raw fox fur" at the well, and you find your self equiping a "delicious deer dog" when you want some light and have just clicked on a torch.
Of course the graphics show your torch flying through the air, not the deer dog from your inventory beside it, so the bug causes no problems. It has just caused me considerable merriment to be informed that my torch is really a sausage or some other absurd piece of misinformation.
It's just a little exasperating though to mouse over my food bar trying to find out if I have 37/47 of a charisma increase yet only to be told "quiver" "cast iron" and "yarn" instead. The fix for that is easy. You just have to move or close the inventory window underneath.