Downloading gitlab designs images to create an offline documentation

I am working from the gitlab instance of kde for our program GCompris.
We are using gitlab wiki and the issues to develop gcompris new control panel specification documentation.
We are trying to use a script to extract the specification structure from the wiki, and insert the issues and the designs into a latex offline documentation.
Wiki and issues extractions are straight forward (md files and csv files), but I do not manage to get the designs pictures path from a command line, just if I use the dev tools from firefox.
I can not find any rest api to deal with designs
Does anybody knows where I can find links such as
I found the link in the download button of but can not download the html part of this page containing the link.

Your help would allow us to have an always up to date offline documentation to give to teachers.