/admin/carts is a super admin only inspector of every cart in the system (open and closed). It has a Users multi-select filter and a Search box, and lists Id, User, Total, Customer Order (the order number if the cart was checked out) and Date; more rows load as you scroll. Clicking a cart Id opens Carts - <id>, a raw dump of the cart contents (days, items, discounts, taxes, coupons, tip, payment method…). It is a support/debugging tool; regular admins are redirected to the login page.