Improved pull request “Files changed” – February 5 updates

Source: GitHub Changelog

This release brings CODEOWNERS validation to the new “Files changed” experience and includes broad performance improvements across common review workflows. Navigation between pull request tabs is faster and more reliable, especially when moving between Conversations and Files changed. Review interactions are smoother for the largest pull requests, with better scrolling, reduced memory usage, and overall stability improvements.

🗂️ Codeowner validation

We added CODEOWNERS validation, filling a gap from the classic “Files changed” experience. Required reviewers are now correctly surfaced based on CODEOWNERS rules, ensuring review requirements are accurately enforced before merge.

📲 Small screens improvements

We are rolling out improvements to the “Files changed” experience on small screens by fixing multiple layout, spacing, and overflow issues, ensuring diffs, comments, headers, and controls render and behave correctly on mobile and smaller viewports.

🚀 Performance improvements

Performance is a top priority for us. Based on your feedback, we’ve shipped several improvements in the past week that directly address lag issues, with a focus on larger pull requests:

• Pull request diffs have been optimized for greater responsiveness when clicking, typing, and scrolling on the page. Early data shows large pull requests in the new files changed experience respond up to 67% faster to these kinds of interactions.
• Only the largest pull requests use virtualization to enhance performance while scrolling and interacting.
• It’s now quicker to navigate between the Conversations and Files tabs, with load times dropping from 10+ seconds to a few seconds.
• Resizing the file tree is now smoother and more responsive, even for large pull requests with many files.
• Improved performance and stability when reviewing pull requests in Safari.
• Fixed high memory usage when reviewing large pull requests.

🔧 More fixes and improvements

• Fixed: Opening a notification directly into the Files changed tab now marks the notification as read, matching the behavior of the classic experience.
• Fixed: The file diff header is now consistently sticky when scrolling.
• Fixed: Code snippets in thread replies no longer have a background color that is hard to distinguish from the reply background.
• Fixed: An error that occurred when commenting across large index differences in diffs has been resolved.

❤ Feedback

Your feedback is important. You can report problems, ask questions, and view known issues in the “Files changed” preview feedback discussion.