Samples of gitlab instance not implementing it (yet?):
- https://0xacab.org/api/v4/projects/
- https://framagit.org/api/v4/projects/
- https://salsa.debian.org/api/v4/projects/
- https://gitlab.com/api/v4/projects/
- https://gitlab.freedesktop.org/api/v4/projects/
- https://gitlab.gnome.org/api/v4/projects/
- https://gitlab.inria.fr/api/v4/projects/
Related T989