What is that little button with the N on it? (by target frame)
There is a personal experiment :cool:
Using underhood I have created a square that become red if I have the aggro.
The letter inside changes from N (Normal) to V (Poison), M (Curse) , E (disease) or M (magic) if I have any debuff.
The letters change with its corresponding colour ( the initials I use are the spanish's debuff type name initials )