Any public post with a photo will automaticly shorten your https://diasp.org/p/fjsajfoidsjfosdijf to a short URL.
You can now also shorten ANY url in a post by adding an extra / to the link so http:///www.fooooooooo.bar.com would be shortened due to the /// after the http: works with http:/// and https:/// and ftp:///
David