thx - i have found the file now:

+ I just add a simple "Hello world" to the file and saved it on line 260 (before Payment Communication)

+ When I create an invoice the "Hello World" is not shown?

do i have to click somewhere that the file is live?

Navigate to Settings --> Technical --> Actions --> Reports (in Developer Mode) to see each Report

The main Invoices report has the template name "account.report_invoice_with_payments" which means it is defined in the account module.

You can find the XML at addons/account/views/report_invoice.xml

Hi,

You can find the invoice template in the following path:  /odoo/addons/account/views/report_invoice.xml

name of the template:  report_invoice_document

* To find the template of any report, you can do as follows
* activate the developer mode
* navigate to Reports menu under settings -> technical
* search and open the report
* by clicking the Qweb Views smart button, you can see the templates used

Thanks