It seems that there was an issue with the information provided about the Pull Request for the thanos-io/thanos project. The term “undefined” does not give me any details about the PR itself.

To create a summary suitable for an advanced developer, I would typically need information about:

1. Purpose of the PR: What problem does it address or what feature does it introduce?
2. Key Changes: What modifications were made to the codebase?
3. Impact: What are the expected outcomes or effects of this PR?
4. Related Issues: Is there a corresponding issue or task this PR is associated with?
5. Testing: Any details on tests added or existing tests modified?
6. Backward Compatibility: Does it introduce any breaking changes?

If you can provide any specific details about the Pull Request, I would be happy to summarize it effectively.