Me too - sorta.
Using waterfox, a firefox fork. Shut down AVG even. Tried .png and .gif. Tried stock avatar, default avatar, no avatar. Won't accept new image file. Try again a few days later and it goes swimmingly. Almost like you can change your avatar only once every so many days. Did this to me before the last upgrade and when I used firefox..
Barely a minor annoyance, just wanted to fill in some symptoms.
