As far as I know mail.templates are now QWeb templates in odoo 12. I found this module but it didn't work neither in the community nor in the enterprise version:

https://www.odoo.com/apps/modules/12.0/mail_debrand/

How is it possible to remove the odoo logo and the "Powered by odoo" at the bottom of the template? I tested it with the Sales Order Template btw.

Thanks for any kind of help.