Commenting on a pull request - GitHub Docs

About status checks - GitHub Docs

Best Practices for Reviewing Pull Requests in GitHub - Rewind

How To Create A Pull Request on Github: Propose Changes to GitHub

Pull Request Diff Comments - The GitHub Blog

GitHub Code Review Best Practices

Work with GitHub pull requests

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Feedback: Comments on individual commits (made outside a pull

Changing the stage of a pull request - GitHub Docs