Ok so I'm testing out Jzargo's scrolls and get too close to an undead when I cast it and I light on fire as well. I don't mind being on fire I guess, but then Lydia gets too close to me while I'm on fire and she catches on fire, I get some message that she leaves my service, and then she starts attacking me to the death because she thinks I was attacking her. I have no way to yield, no way to talk to her, and it's ridiculous. The damage she took should have been considered as "enemy fire" and not considered "friendly fire".
I'm pretty forgiving with bugs, but I value my companions and I think this should be fixed. The engine acted like I struck her with my sword 10 times in a row.