Make an animated JPG and upload to Facebook : Imposter GIFs

A friend asked me on Facebook :

How to upload GIFs to Facebook?

Does not facebook block all non JPG/PNG graphic uploads? Then how to people upload images like this one to facebook?

That was not the first time I had come across an animated image on Facebook. Orkut and Google+ used to the only places where we used to get pelted with these resource crunching GIFs. I even knew for sure Facebook does not allow Gifs. So I did a little digging.

It turns out that the Facebook developers overlooked a tiny loophole in the file formats.
A GIF, you see, can be forcefully saved as .JPG. While it still retains its animation information and filetype as GIF.
Try to open any animated JPG file like this one . I just used a free GIF file and saved it as .JPG.

This is an IMPOSTER GIF. A GIF that pretends to be a JPG.
Wordpress knows what it is. If you try to upload an Imposter Gif to wordpress it will smartly rename it to .gif.
Facebook knows that too. But if you mess around with the header information of the GIF file well enough you can convince Facebook that the GIF is actually a JPG image.

Warning : If you try hoodwinking Facebook multiple times you will be banned. 

It turns out that there are certain ways of uploading such a JPG to Facebook. The most common was is to use such images through facebooks apps. You cannot save an animated JPG already on Facebook to your hard disk and then upload it again to Facebook.

Here is a Video that may work for you. This method exploits a source hack. Try these at your own risk.