https://github.com/QtExcel/QXlsx/commit/90d762625750c6b2c73f6cd96b633e9158aed72e

Index: QXlsx/CMakeLists.txt
--- QXlsx/CMakeLists.txt.orig
+++ QXlsx/CMakeLists.txt
@@ -17,6 +17,11 @@ if(NOT DEFINED QT_VERSION_MAJOR)
     find_package(QT NAMES Qt6 Qt5 COMPONENTS Core Gui REQUIRED)
 endif()
 find_package(Qt${QT_VERSION_MAJOR} COMPONENTS Core Gui REQUIRED)
+
+if(Qt6Gui_VERSION VERSION_GREATER_EQUAL "6.10.0")
+    find_package(Qt6 REQUIRED COMPONENTS GuiPrivate)
+endif()
+
 set(EXPORT_NAME QXlsxQt${QT_VERSION_MAJOR})
 
 if (QT_VERSION_MAJOR EQUAL 6)
