Hello again :-)
Since the German Parliament has passed laws requiring invoices to be sent and received in a specific format (XInvoice and/or ZUGFeRD), it might be good for ITFlow to address this topic. This issue affects all Geman companies and should be implemented by the end of 2027. More information on this:
https://stripe.com/resources/more/xml-invoice
https://en.e-rechnung-bund.de/e-invoicing-faq/xrechnung/
Possibly, I could contribute to the development costs. Please let me know.