I’m migrating TFS repositories that use a Git source control over to GitHub and noticed that the contributors of the TFS repository get added to the list of contributors on GitHub. However, the contributors are not listed as collaborators. I presume it’s because of the .git folder that has that metadata about contributors and GitHub recognizes that the contributors’ emails match to those of my members in my organization. Not seeing any clear documentation though.

Also, how can I get those contributors to be automatically added to the collaborator list in GitHub upon migration? (i.e. after a git clone and git push of all the contents from TFS to GitHub)