From c48337fdc6a53a4bc86e575fa7b9ccad4f415acc Mon Sep 17 00:00:00 2001
From: lhark <lhark@lharktop>
Date: Sat, 1 Oct 2022 21:56:15 +0200
Subject: [PATCH] PDF decryption

---
 how_to | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/how_to b/how_to
index caf9cf7..d9d03aa 100644
--- a/how_to
+++ b/how_to
@@ -287,6 +287,10 @@ PDF :
         Master PDF Editor (free version):
             https://code-industry.net/free-pdf-editor/
             trizen -S masterpdfeditor
+    Decrypt pdf files:
+        # For example when pdftk spews this error:
+        # `Error: Invalid PDF: unknown.encryption.type.r`
+        qpdf --decrypt input.pdf output.pdf
 
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