Author: Michael R. Crusoe <michael.crusoe@gmail.com>
Description: Use the packaged version of cppreference
--- seqan3.orig/test/documentation/seqan3-doxygen.cmake
+++ seqan3/test/documentation/seqan3-doxygen.cmake
@@ -34,16 +34,11 @@
 include(ExternalProject)
 ExternalProject_Add (
     download-cppreference-doxygen-web-tag
-    URL "https://github.com/PeterFeicht/cppreference-doc/releases/download/v20190928/html-book-20190928.tar.xz"
-    URL_HASH SHA256=6c250b02f6cb0fb54ea372d81c8f50703c01cc9f6887281c88a84dd91f463abc
-    TLS_VERIFY ON
-    DOWNLOAD_DIR "${PROJECT_BINARY_DIR}"
-    DOWNLOAD_NAME "html-book.tar.xz"
-    DOWNLOAD_NO_EXTRACT YES
+    DOWNLOAD_COMMAND ""
     BINARY_DIR "${PROJECT_BINARY_DIR}"
-    CONFIGURE_COMMAND /bin/sh -c "xzcat html-book.tar.xz | tar -xf - cppreference-doxygen-web.tag.xml"
-    BUILD_COMMAND rm "html-book.tar.xz"
-    INSTALL_COMMAND ""
+    CONFIGURE_COMMAND ""
+    BUILD_COMMAND ""
+    INSTALL_COMMAND ln -s /usr/share/devhelp/books/cppreference-doxygen-web.tag.xml "${PROJECT_BINARY_DIR}/"
 )
 
 if (SEQAN3_USER_DOC)
