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The standard GitHub keywords for linking and closing issues are supported.
Only one issue should be included per keyword. If multiple issues are included for a keyword, GitHub will only close the first issue in the list.
Only referenced GitHub issues are closed.
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Once you've identified the issue / epic to reference(s), you can either update the PR body with the reference or amend their commit(s) with the reference(s). If you’d you'd like, you may let them know you made the edits.