See https://docs.gitlab.com/ee/ci/ci_cd_for_external_repos/

This feature currently does not support Pull Requests from fork repositories. Any Pull Requests from fork repositories are ignored.

We use GitLab CI for pypy tests, because GitHub actions is extremely slow for pypy tests (20min, vs GitLab CI's 3min).

This is not urgent for us, but it would matter when we start accepting pull requests from outside people.

It looks like someone has already started working on this feature: https://gitlab.com/gitlab-org/gitlab/-/issues/5667 Since it's nor urgent anyway, we can wait for a bit to see whether they would fix this issue before it becomes relevant.