I have noticed that there is a cmake target called XcbQpaPrivate, and I think there should be headers to use, because it even has no so for it, so headers are needed. but after installed , there is not header for it.

In Qt5, on archlinux, there is a package called qt5-xcb-private-headers, but now there is no that package, because the headers are not installed, so I think it maybe a bug

https://github.com/qt/qtbase/blob/5bb71bb88e965fd43605af2eba80c5e7a3df64bf/src/plugins/platforms/xcb/CMakeLists.txt#L103