Refunding a Store order failed with "Stripe payment does not match this order" for every order. Refunds now go through.
When a buyer changed their cart after starting checkout, returning to checkout reopened the earlier payment page for the old items and total. The earlier checkout is now ended and a new one opens for the cart as it is.
An unpaid checkout now ends 30 minutes after it starts, and its items are returned to stock; before, they could stay held for up to a day.