Create a document from an embedded task form

Hi again @martin.stamm,

My exact purpose is to produce a pdf document (with iText library maybe) from an html task form like the following:

This task form is displayed when the user loads his form in “Receive the Selected Products” User Task:

So, I don’t want to create an empty pdf document but to convert the above html form.
Must I do sth before the conversion (such as to get the task form in the form of a file by REST API call for example) ?

Thanks a lot,
Steve