On out of the box entities, when adding the stock 'Status' field to the header it causes the header to display an additional tab (in addition to the read-only version) called Header containing all the header fields. On custom entities this is not an issue, the header is displayed in its read-only state. Removing the 'Status' field makes the issue go away. I see this on 2 instances I tested, both UR13 5.0.9690.3351
Anyone with some potential insight?