It has crashed because I had previously run gnome-boxes as root (sudo gnome-boxes), this changed owner of the folder ~/.local/share/gnome-boxes/images to root instead of current user.
Simply chowning this folder to current user fixed the issue.
It has crashed because I had previously run gnome-boxes as root (sudo gnome-boxes), this changed owner of the folder ~/.local/ share/gnome- boxes/images to root instead of current user.
Simply chowning this folder to current user fixed the issue.