After logging in and visiting the CiviCRM dashboard, I see this message:
You do not have permission to view this contact record. Contact the site administrator if you need assistance.
The error appears harmless ("If I simply ignore it and carry on then all seems fine." as the SE question says).
I see this when visiting the dashboard on CiviCRM.org, and saw an SE question on it so figured I'd log the bug.
I don't intend debugging this on CiviCRM.org live site, but will if I run into it somewhere I'm able to readily OR if assisted with access to a test copy of the CiviCRM website.