In the bom cost report template, a "tr" is missing and no parent_id for the subcontructing part. This result in a leftover line each time you fold the bom. Add them to the tamplate. Task-2657280 X-original-commit: 6ae623dc2d5131e2b11969f1bc1f8dd6096a9005 Part-of: odoo/odoo#77945