I made one small change to the existing template, but now it is not translated anymore in Dutch. How can i achieve this?
You cannot. The sample template that appears if your create a new view template is only an example. It is not the HTML being used to generate the standard invoice. So it does not call up all the features of the standard invoice. If you want changes AND translation, you will need to rewrite the template from scratch.
Still, it would be very nice if the initial template would be generated in the currently selected language, right?
Although this is definitely a nice to have