I MC’d a mob in Bot to buff some members of my group with Holy Fury (which gives a slot of Spell Power), the mob also happened to have a Greater Heal ability. I used it once to heal the tank while I was still on the mob.
Shortly there after I noticed that my shift modifier GH macro that uses max rank by not putting a rank, was trying to use the GH ability from the MC’d mob, not my max rank GH.
Reloading the UI didn’t resolve it, I had to log out and back in to get my normal max rank GH use back for that macro.
Edit: Didn’t notice it switched back to my old retail character instead of my Classic TBC character.