[philja]

I've removed the -DUSE_SYSTEM_LIBS=1 from the command line. I've installed the qt6-webengine-dev-tools package. I deleted the old sigil-build directory and made a new one. Then I ran the cmake again.

This time, all bundled hunspell, pcre3, zlib, minizip were used. The failures were the same with one extra I didn't see last time (under using bundled ZLIB):

Check size of off64_t - failed

The CMakeError.log has a mention of this:

 Entering directory '/home/pnj/sigil-build/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_58f66.dir/OFF64_T.c.o
/usr/bin/cc    -o CMakeFiles/cmTC_58f66.dir/OFF64_T.c.o -c /home/pnj/sigil-build/CMakeFiles/CheckTypeSize/OFF64_T.c
/home/pnj/sigil-build/CMakeFiles/CheckTypeSize/OFF64_T.c:27:22: error: ‘off64_t’ undeclared here (not in a function); did you mean ‘off_t’?
   27 | #define SIZE (sizeof(off64_t))

The others were the same:

 Using Bundled PCRE2
-- Looking for dirent.h
-- Looking for dirent.h - found
-- Looking for inttypes.h
-- Looking for inttypes.h - found
-- Looking for sys/stat.h
-- Looking for sys/stat.h - found
-- Looking for unistd.h
-- Looking for unistd.h - found
-- Looking for windows.h
-- Looking for windows.h - not found
-- Looking for C++ include type_traits.h
-- Looking for C++ include type_traits.h - not found
-- Looking for C++ include bits/type_traits.h
-- Looking for C++ include bits/type_traits.h - not found

and

 Looking for _strtoi64 - not found

Then the red part of the consol output has completely changed:

CMake Error at /usr/lib/x86_64-linux-gnu/cmake/Qt6LinguistTools/Qt6LinguistToolsTargets.cmake:131 (message):
  The imported target "Qt6::lconvert" references the file
     "/usr/lib/qt6/bin/lconvert"
  but this file does not exist.  Possible reasons include:
  * The file was deleted, renamed, or moved to another location.
  * An install or uninstall procedure did not complete successfully.
  * The installation package was faulty and contained
     "/usr/lib/x86_64-linux-gnu/cmake/Qt6LinguistTools/Qt6LinguistToolsTargets.cmake"
  but not all the files it references.

Call Stack (most recent call first):
  /usr/lib/x86_64-linux-gnu/cmake/Qt6LinguistTools/Qt6LinguistToolsConfig.cmake:47 (include)
  /usr/lib/x86_64-linux-gnu/cmake/Qt6/Qt6Config.cmake:219 (find_package)
  src/qt6sigil.cmake:27 (find_package)
  src/CMakeLists.txt:685 (include)

There was no orange colored output this time. So it looks like the Qt6WebEngine problem has disappeared.