In Search For Print Invoice Template

I am looking for the template that prints the invoice from the link [store]/index.php?dispatch=orders.print_invoice&order_id=xxx. I am using the template mode 'New (nice and editable in the Editor panel). Editing "orders/invoice.tpl" leads to no change. The cache was cleared. Any input is appreciated. Tx.

The template is stored in the database. Please changes corresponding document on the Administration -> Notifications -> Documents page

Thank you. That is the one.