File header takes less width than available in diff section #2496

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Confirmed that bug is caused by Refined GitHub, as it's not reproducible with the extension disabled.

URL here bug appears https://github.com/aws/aws-sdk-js-v3/pull/404/files/c76e142623095f22ade1532079a262d678877276..d481a6ab569e7bef240f9a8170ae14069e0f9e6a

• This issue happens in "changed since last view" URL, user will have view some files in previous diff to reproduce this issue.
• Not reproducible in default diff URL https://github.com/aws/aws-sdk-js-v3/pull/404/files