How to associate an image (PNG, not docker!) with a repo in the container list

Hi, I’ve got a project on the Dockerhub:

I’d like it to have an image associated with it in the list of containers in the left sidebar Kitematic. For example, it might be a book cover image, like this:

Basically, I want the container to have an associated icon, the way you do for some of the main images.

I haven’t been able to find this anywhere, so any thoughts on if this is possible?

I would like to do the same, but I think that there is no documentation on how to do this.

I have some docker images that are for teaching purposes and making the image look cool on kitematic would be very very nice!