Header private/qhexstring_p.h is not found.

[怕什么真理无穷]

编译OpenBoard-master 时候，Project ERROR: Unknown module(s) in QT: webkit webkitwidgets
找到对应的qtwebkit-dev进行编译时，打印：
CMake Error at Source/cmake/OptionsQt.cmake:100 (message):
Header private/qhexstring_p.h is not found. Please make sure that:

1. Private headers of Qt5Gui are installed
2. Qt5Gui_PRIVATE_INCLUDE_DIRS is correctly defined in Qt5GuiConfig.cmake
Call Stack (most recent call first):
Source/cmake/OptionsQt.cmake:652 (CHECK_QT5_PRIVATE_INCLUDE_DIRS)
Source/cmake/WebKitCommon.cmake:53 (include)
CMakeLists.txt:137 (include)


怎么解决？类似搜到一个，不太会改动。
https://codereview.qt-project.org/c/qt/qtbase/+/227458/4/mkspecs/features/create_cmake.prf#b58