[Sakib-invento]

Summary

• 1.1.2 set quotation.flags.ignore_permissions, but that only covers permission checks on the Quotation document itself.
• The actual failure, confirmed via a full traceback captured directly on production (ERPNext 16.35.0), is erpnext.stock.get_item_details.get_item_details() calling item.check_permission() on a separate Item document - a check that flag never reaches. Dev runs an older ERPNext (16.19.1) without that check, which is why it never reproduced there.
• place_order() now runs quotation building, pricing/tax calculation and submission under a temporary Administrator elevation (_run_as_system_user()), restored to the real session user immediately after. Checkout no longer depends on which Item (or other business doctype) permissions happen to be configured for a customer's role on a given site.

Release 1.1.3.

Test plan

• Reproduced the exact live traceback via bench console on the production site itself (same account that failed in the browser), confirming item.check_permission() in get_item_details.py as the failure point.
• Verified locally end-to-end with the fix: guest signup + order succeeds, Portal User row is created, and the session correctly restores to the real customer (not stuck as Administrator) once the elevated block exits.