How can I limit the allowed quantity in the cart to one item? I am using Drupal 8/Commerce 2. How do I limit the quantity in the cart to one item so that users can't order more than one item per order.
Drupal 8 / Commerce have field "Default quantity to add to cart", so you can add default quantity for product is 1 and hide it from product page. After that user can't change quantity of products. Problem is solved!