Oddest thing I have seen. The surface of the mirror seems to have some liquid over it, how it auto-dims no doubt, and that was boiling in the bottom right corner of the mirror!!
I was worried I was about to loose the car.. garage.. house.. neighbour for a minute..
DEFINATELY going to get a car extinguisher now!!
Was waiting for that mirror to go all fuzzy like the nearside one I already replaced, but guess I will be replacing it sooner now!