I have already signed PDF file with qualified certs in PADES format.
I need add stamp, annotation, new layer to this PDF document. The signature became broken.
My question is how to add stamp, annotation or new layer to this PDF document without loosing the validity of qualified signature ?
My only way is that I do what I need but add copy of not changed document as an attached file. This way has one big inconvenience double the size of the target document
Does anyone have a better solution? What I mean here is some internal versioning in the document that will allow you to keep/see the original document before the changes were made, i.e. still containing the correct PADES with valid signature.
