It is an animated GIF image, I find some premade animated GIFs and then use my free GIMP software -
https://www.gimp.org/ to edit the GIF to put the members face over the original face.
Then if I need to crop, resize, or otherwise modify the animated GIF I use this free web site -
https://ezgif.com/ then I add it to a free photo hosting site and add the IMG link to the post, that way I can post animated GIFs that would be too large for the forum to accept as a direct upload. The very small animated icons are small enough that I can upload them directly.
......and yes, I do have an animated Coinboy one made I can post tomorrow
(I also have a Scuba, Mud, and another Dave animated edits to post over the coming week, with more animated GIFs I have to yet edit as I have time)