diff --git a/CMakeLists.txt b/CMakeLists.txt
index 794ac6eb5..1b3545c67 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -58,7 +58,6 @@ find_package(
   QT
  NAMES
   Qt6
-  Qt5
  COMPONENTS
   ${QET_COMPONENTS}
  REQUIRED
@@ -71,9 +70,10 @@ find_package(
  REQUIRED)
 
 set(CMAKE_AUTOUIC_SEARCH_PATHS ${QET_DIR}/sources/ui)
-qt5_create_translation(QM_FILES ${CMAKE_SOURCE_DIR} ${TS_FILES})
+
+qt_create_translation(QM_FILES ${CMAKE_SOURCE_DIR} ${TS_FILES})
 set_source_files_properties(${TS_FILES} PROPERTIES OUTPUT_LOCATION "${QET_DIR}/lang")
-qt5_add_translation(QM_FILES ${TS_FILES})
+qt_add_translation(QM_FILES ${TS_FILES})
 
 # als laatse
 include(cmake/define_definitions.cmake)
@@ -92,7 +92,7 @@ target_link_libraries(
   PRIVATE
   pugixml::pugixml
   SingleApplication::SingleApplication
-  ${KF5_PRIVATE_LIBRARIES}
+  ${KF6_PRIVATE_LIBRARIES}
   ${QET_PRIVATE_LIBRARIES}
   )
 
diff --git a/cmake/define_definitions.cmake b/cmake/define_definitions.cmake
index 7f9cb6ae0..94550bbde 100644
--- a/cmake/define_definitions.cmake
+++ b/cmake/define_definitions.cmake
@@ -62,8 +62,8 @@ message("PROJECT_SOURCE_DIR        :" ${PROJECT_SOURCE_DIR})
 message("QET_DIR                   :" ${QET_DIR})
 message("GIT_COMMIT_SHA            :" ${GIT_COMMIT_SHA})
 
-if(BUILD_WITH_KF5)
-  message("KF5_GIT_TAG               :" ${KF5_GIT_TAG})
+if(BUILD_WITH_KF6)
+  message("KF6_GIT_TAG               :" ${KF6_GIT_TAG})
 else()
   add_definitions(-DBUILD_WITHOUT_KF5)
 endif()
diff --git a/cmake/developer_options.cmake b/cmake/developer_options.cmake
index 04f002da4..677c61f93 100644
--- a/cmake/developer_options.cmake
+++ b/cmake/developer_options.cmake
@@ -31,5 +31,5 @@ add_definitions(-DQT_MESSAGELOGCONTEXT)
 # In order to do so, uncomment the following line.
 #add_definitions(-DTODO_LIST)
 
-# Build with KF5
-option(BUILD_WITH_KF5 "Build with KF5" ON)
+# Build with KF6
+option(BUILD_WITH_KF6 "Build with KF6" ON)
diff --git a/cmake/fetch_kdeaddons.cmake b/cmake/fetch_kdeaddons.cmake
index ac5a340f9..6ea692f8f 100644
--- a/cmake/fetch_kdeaddons.cmake
+++ b/cmake/fetch_kdeaddons.cmake
@@ -16,52 +16,43 @@
 
 message(" - fetch_kdeaddons")
 
-if(DEFINED BUILD_WITH_KF5)
+if(DEFINED BUILD_WITH_KF6)
   Include(FetchContent)
 
-  option(BUILD_KF5 "Build KF5 libraries, use system ones otherwise" YES)
+  option(BUILD_KF6 "Build KF6 libraries, use system ones otherwise" NO)
 
-  if(BUILD_KF5)
+  if(BUILD_KF6)
 
-    if(NOT DEFINED KF5_GIT_TAG)
-      #https://qelectrotech.org/forum/viewtopic.php?pid=13924#p13924
-      set(KF5_GIT_TAG v5.77.0)
+    if(NOT DEFINED KF6_GIT_TAG)
+      set(KF6_GIT_TAG v6.5.0)
     endif()
 
-    # Fix stop the run autotests of kcoreaddons
-    # see
-    # https://invent.kde.org/frameworks/kcoreaddons/-/blob/master/CMakeLists.txt#L98
-    # issue:
-    # CMake Error at /usr/share/ECM/modules/ECMAddTests.cmake:89 (add_executable):
-    # Cannot find source file:
-    # see
-    # https://qelectrotech.org/forum/viewtopic.php?pid=13929#p13929
-    set(KDE_SKIP_TEST_SETTINGS "TRUE")
-    set(BUILD_TESTING "0")
+    # 
+    set(BUILD_TESTING OFF)
     FetchContent_Declare(
       ecm
       GIT_REPOSITORY https://invent.kde.org/frameworks/extra-cmake-modules.git
-      GIT_TAG        ${KF5_GIT_TAG})
+      GIT_TAG        ${KF6_GIT_TAG})
     FetchContent_MakeAvailable(ecm)
 
     FetchContent_Declare(
       kcoreaddons
       GIT_REPOSITORY https://invent.kde.org/frameworks/kcoreaddons.git
-      GIT_TAG        ${KF5_GIT_TAG})
+      GIT_TAG        ${KF6_GIT_TAG})
     FetchContent_MakeAvailable(kcoreaddons)
 
     FetchContent_Declare(
       kwidgetsaddons
       GIT_REPOSITORY https://invent.kde.org/frameworks/kwidgetsaddons.git
-      GIT_TAG        ${KF5_GIT_TAG})
+      GIT_TAG        ${KF6_GIT_TAG})
     FetchContent_MakeAvailable(kwidgetsaddons)
   else()
-    find_package(KF5CoreAddons REQUIRED)
-    find_package(KF5WidgetsAddons REQUIRED)
+    find_package(KF6CoreAddons REQUIRED)
+    find_package(KF6WidgetsAddons REQUIRED)
   endif()
 
-  set(KF5_PRIVATE_LIBRARIES
-    KF5::WidgetsAddons
-    KF5::CoreAddons
+  set(KF6_PRIVATE_LIBRARIES
+    KF6::WidgetsAddons
+    KF6::CoreAddons
     )
 endif()
diff --git a/tests/catch/CMakeLists.txt b/tests/catch/CMakeLists.txt
index b6ab66bf0..b2d0cc2d1 100644
--- a/tests/catch/CMakeLists.txt
+++ b/tests/catch/CMakeLists.txt
@@ -45,7 +45,6 @@ if(NOT DEFINED QT_VERSION_MAJOR)
     QT
    NAMES
     Qt6
-    Qt5
    COMPONENTS
     ${QET_COMPONENTS}
    REQUIRED
@@ -88,7 +87,7 @@ target_link_libraries(
     PUBLIC
     Catch2::Catch2
     PRIVATE
-    ${KF5_PRIVATE_LIBRARIES}
+    ${KF6_PRIVATE_LIBRARIES}
     ${QET_PRIVATE_LIBRARIES})
 
 if (DEFINED ENV{CATCH_INCLUDE_DIR})
diff --git a/tests/googlemock/CMakeLists.txt b/tests/googlemock/CMakeLists.txt
index db29ef8c9..c364fee37 100644
--- a/tests/googlemock/CMakeLists.txt
+++ b/tests/googlemock/CMakeLists.txt
@@ -45,7 +45,6 @@ if(NOT DEFINED QT_VERSION_MAJOR)
     QT
    NAMES
     Qt6
-    Qt5
    COMPONENTS
     ${QET_COMPONENTS}
    REQUIRED
@@ -85,6 +84,6 @@ target_link_libraries(
     PUBLIC
     gmock gmock_main
     PRIVATE
-    ${KF5_PRIVATE_LIBRARIES}
+    ${KF6_PRIVATE_LIBRARIES}
     ${QET_PRIVATE_LIBRARIES})
 
diff --git a/tests/googletest/CMakeLists.txt b/tests/googletest/CMakeLists.txt
index d9a4ae750..cd7a8beab 100644
--- a/tests/googletest/CMakeLists.txt
+++ b/tests/googletest/CMakeLists.txt
@@ -45,7 +45,6 @@ if(NOT DEFINED QT_VERSION_MAJOR)
     QT
    NAMES
     Qt6
-    Qt5
    COMPONENTS
     ${QET_COMPONENTS}
    REQUIRED
@@ -84,6 +83,6 @@ target_link_libraries(
     PUBLIC
     gtest gtest_main
     PRIVATE
-    ${KF5_PRIVATE_LIBRARIES}
+    ${KF6_PRIVATE_LIBRARIES}
     ${QET_PRIVATE_LIBRARIES})
 
diff --git a/tests/qttest/CMakeLists.txt b/tests/qttest/CMakeLists.txt
index 41137a3e5..88e8981ea 100644
--- a/tests/qttest/CMakeLists.txt
+++ b/tests/qttest/CMakeLists.txt
@@ -45,7 +45,6 @@ if(NOT DEFINED QT_VERSION_MAJOR)
     QT
    NAMES
     Qt6
-    Qt5
    COMPONENTS
     ${QET_COMPONENTS}
     Test
@@ -74,6 +73,6 @@ target_link_libraries(
   ${PROJECT_NAME}
   PRIVATE
   Qt::Test
-  ${KF5_PRIVATE_LIBRARIES}
+  ${KF6_PRIVATE_LIBRARIES}
   ${QET_PRIVATE_LIBRARIES})