kdeltachat build error

gistfile1.txt

~/Downloads/kdeltachat $ cmake -B build .
Installing in /usr/local. Run /home/me/Downloads/kdeltachat/build/prefix.sh to set the environment for kdeltachat.
CMake Error at /usr/lib/cmake/Qt6Qml/Qt6QmlMacros.cmake:2535 (message):
  qt_generate_foreign_qml_types() is only available in Qt 6.
Call Stack (most recent call first):
  /usr/lib/cmake/Qt6Qml/Qt6QmlConfig.cmake:132 (include)
  /usr/share/cmake/Modules/CMakeFindDependencyMacro.cmake:76 (find_package)
  /usr/lib/cmake/Qt6/QtPublicDependencyHelpers.cmake:111 (find_dependency)
  /usr/lib/cmake/Qt6Quick/Qt6QuickDependencies.cmake:39 (_qt_internal_find_qt_dependencies)
  /usr/lib/cmake/Qt6Quick/Qt6QuickConfig.cmake:50 (include)
  /usr/lib/cmake/Qt6/Qt6Config.cmake:174 (find_package)
  CMakeLists.txt:22 (find_package)


CMake Warning at /usr/lib/cmake/Qt6/Qt6Config.cmake:174 (find_package):
  Found package configuration file:

    /usr/lib/cmake/Qt6Quick/Qt6QuickConfig.cmake

  but it set Qt6Quick_FOUND to FALSE so package "Qt6Quick" is considered to
  be NOT FOUND.
Call Stack (most recent call first):
  CMakeLists.txt:22 (find_package)


-- Configuring incomplete, errors occurred!