Q:

Why do no browsers apart from Firefox support animated PNGs?

When I look into the list (http://caniuse.com/apng) of supported browser on animated PNG, I found that basically only Firefox support it. All the other major browsers don't support. Even the Opera which they once support it and they drop it on newer release.
I always thinking animated PNG is nice. But why is most browsers don't support it? What is the reason they not support?

A:

Google developers discussed it here:
https://groups.google.com/a/chromium.org/forum/#!msg/chromium-dev/2xvXNJMsgxc/2CJ9jl-jItcJ

