PDF

• xournal - add notes on PDF documents

sudo apt install qpdf
qpdf --password-file=- --decrypt encrypted.pdf decrypted.pdf

convert-im6.q16: attempt to perform an operation not allowed by the security policy `PDF' @ error/constitute.c/IsCoderAuthorized/421.

Workaround:

/etc/ImageMagick-6/policy.xml

<policy domain="coder" rights="read|write" pattern="PDF" />