I have a few hundred pages of highly annotated PDF file, which is mostly text, in the form of underlines, highlights, and (more) text annotations.
After two years, a updated version of that document came out, with some revisions to the text.
Question: Is there a way for me to export my annotations from the old version of the PDF and import it to the new one?
(And if anyone has an idea, how are annotations stored anyway in PDFs at the file-structure level? Can it be exported? I'm on Linux by the way and am comfortable with advanced command line tools if need be.)