I tried a virtual machine with my system configuration during 4 hours and couldn't reproduce the leak (I used "guix system vm"). ".gnome-shell-real" kept using about 260 MiB of RAM and it actually went down to 220 at some point.
In 4 hours, in my real system, the leak would have been visible. I'm planning to create another virtual machine with "guix system vm-image" instead to install all the packages I have in my user profile and leave it running overnight to see if there is any difference.
