developer-manual: Bump copyright

diff --git a/doc/source/developer-manual.sgml b/doc/source/developer-manual.sgml
index 30af615..87c34b8 100644 (file)
--- a/doc/source/developer-manual.sgml
+++ b/doc/source/developer-manual.sgml
@@ -19,7 +19,7 @@
 
  Purpose     :  developer manual
 
- Copyright (C) 2001-2021 Privoxy Developers https://www.privoxy.org/
+ Copyright (C) 2001-2023 Privoxy Developers https://www.privoxy.org/
  See LICENSE.
 
  ========================================================================
@@ -39,7 +39,7 @@
     <!-- Completely the wrong markup, but very little is allowed  -->
     <!-- in this part of an article. FIXME -->
       <ulink url="https://www.privoxy.org/user-manual/copyright.html">Copyright</ulink>
-      &my-copy; 2001-2021 by
+      &my-copy; 2001-2023 by
       <ulink url="https://www.privoxy.org/">Privoxy Developers</ulink>
      </subscript>
     </pubdate>