This is simple hack to embeed GPG clear signature to PDF file.
Such signed PDF files can be easily verified by $gpg --verify file.pgp.asc.pdf
gpg --clearsign substitutes "\n-" with "\n- -", which mess content quite often. Sometimes it's better to substitute "\n-" patterns with something different before clearsign kicks-in. This simple script substitutes such patterns before clearsigning
Please be aware, that this can mess-up contents of your PDF, so try different substitution pattern by flipping bits, and checking if your PDF is still readable, or try to adapt your document before signing. Usually this pattern is used to mark default color of text, so try to change style of "Default" font from "Automatic" to "Black".
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