After many researchs on Internet, I have not found an answer to how to use the upload function, in order to do a mail merge based on an existing Word document.
Print/Merge document has an option to upload a .docx word file. But I have not figured out how to use it.
Is is possible to create a Word document and somehow add the tokens directly in this document? And then do the merge via the upload? Thanks for your help. (Drupal 7.67 & Civi 5.7.0)