Produce or register credentials for git2rSource:
In usethis v2.0.0, usethis switched from git2r to gert (+ credentials) for all Git operations. This pair of packages (gert + credentials) is designed to discover and use the same credentials as command line Git. As a result, a great deal of credential-handling assistance has been removed from usethis, primarily around SSH keys.
If you have credential problems, focus your troubleshooting on getting the credentials package to find your credentials. The introductory vignette is a good place to start.
If you use the HTTPS protocol (which we recommend), a GitHub personal access
token will satisfy all auth needs, for both Git and the GitHub API, and is
therefore the easiest approach to get working. See