GitHub has updated its functionality for closing issues via commit messages, allowing issues to be automatically closed only when the commit is merged into the default branch, typically "master." This change ensures that an issue's status accurately reflects its resolution in the default branch, preventing premature closure if the fix is not yet merged. If a commit with syntax like "Fixes #33" is made in a non-default branch, the issue is referenced with a tooltip, and users can modify their default branch settings if they primarily work on another branch. The keywords "close," "closes," "closed," "fixes," and "fixed" can all be used to trigger this behavior, providing flexibility in managing issue statuses.