GitHub Copilot can now tell developers when its suggestions match code in a public repository

the launch of a code referencing feature for GitHub Copilot. The key points are:

1. GitHub Copilot previously had a feature that automatically blocked suggestions of matching public code.
2. GitHub has now launched a private beta of a code referencing feature that shows matching code to developers in a sidebar, allowing them to decide what to do with it.
3. This feature will also be added to Copilot Chat in the future.
4. The original blocking feature was seen as a blunt tool, limiting developers' control and preventing them from exploring libraries and submitting pull requests.
5. The code referencing feature allows developers to reject, use directly, or have Copilot rewrite the code to avoid matching the original code.
6. Currently, it is not possible to filter results based on specific licenses, but the team is open to feedback on this.
7. The feature is more likely to generate matching code when there is less context available for Copilot to work with.
8. The feature utilizes a fast search engine to quickly find matching code and its license.
9. The order of the matching code snippets is based on the search engine's findings, but GitHub may add sorting functionality in the future.