Animated favicons are a huge distraction and suck. From the looks of it this project aims to make the favicon display useful information like notification counts instead of animated loops.

Does that work? I thought gifs weren't valid format for a favicon?

They aren't, but many browsers still display them, and last I checked both Firefox and Chrome animate them. You shouldn't use them if you can help it.

So does this js work for IE and Safari? If so, we've got a polyfill!

favicon.ico is a Windows icon, but icons specified in <link rel=icon> don't have to be.

correct