Print an invoice
First create a customer order on the POS.
In backoffice, navigate to Accounts receivable > Orders > All sales orders
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Find and click the sales order.
Click 'invoice' in the header and under the journals section click 'Invoice'.
Under 'Document', click 'View' and then 'Copy preview' to print a copy of the invoice. Click 'Original preview' instead to print the original invoice.