I don't have anything enabled to generate proforma invoices, and yet it's still generating documents with the title "Proforma."
PS: This happens to me with all Odoo installations in version 18, and some only have the billing module, while others have it with the sales, purchasing, and invoicing modules as well.



I'm having the same issue and Odoo says it's standard practice, the workaround seems to print it (don't send) and then it's ok