Have you ever visited some website with lots of banner ads?
Not in recent years, use Adblock 
I used to not mind the advertising, until more and more websites went overboard and became unbearable.Also great in Firefox: about:config > image.animation_mode > once.
I know Theymos disabled animated images for avatars. But, what was the reason behind that? Just because people find it annoying or maybe there were some other issues as well?
Some advertising went crazy with blinking avatars. Animated avatars aren't supposed to be allowed, but I never got around to adding detection for the APNG ones. I'll look into it.
OK, APNGs are now detected. Old ones are grandfathered for now