Where to find GitHub project boards I have been added to as collaborator?

Question

I have created a project board on Github and added another user as a collaborator to this private project. He can't find the project under his own project list but only if I give him the direct link.

Answer 1

Double-check the permission granted for that user for the project, using the GitHub API

But I suspect that, unless your project is an organization project (where you can add a collaborator), a collaborator would not see a private project in their own project list unless given a direct link.