Generate Image Assets not creating .gif files

Hi,

When I have a .psd file open and go to File>Generate>Image Assets

I then select a layer and rename it to something like "guitar.jpg" for example, a folder is created and a .jpg of that layer is generated, but if I rename any of the layers to "guitar.gif" nothing happens.

All other formats work like .png, .jpg etc. but just not .gif