Have no idea, but it is neat. You might try posing a question in the comments at the bottom.
My thinking would be that it is done by using a few of the same pictures and moving parts like the tail and eyelids they going a slide show which plays with no pauses between pictures. Could be totally wrong but think I might have a try to see what happens....
I think it's done with a plug-in that works either within your editing program or as a standalone.
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