Install Qt 6.8.0 gcc binaries including Qt Graphs on linux, configure and compile example graphs/3d/equation

/home/qt/RTA/Qt_6.8.0/6.8.0/gcc_64/bin/qt-cmake -S /home/qt/RTA/Qt_6.8.0/Examples/Qt-6.8.0/graphs/3d/equation -B /home/qt/RTA/Qt_6.8.0/Examples/Qt-6.8.0/graphs/3d/equation/bld_gcc_64 -GNinja

-> ok, build: cmake --build . --parallel -j 8

-> ok, run install command

cmake --install . --prefix /home/qt/RTA/Qt_6.8.0/example_install

in /home/qt/RTA/Qt_6.8.0/Examples/Qt-6.8.0/graphs/3d/equation/bld_gcc_64

-> ok, but when launching /home/qt/RTA/Qt_6.8.0/example_install/examples/equation

-> fails:

qt.qpa.plugin: Could not find the Qt platform plugin "xcb" in ""
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem 

Same with the scatter.

Edit: Other Graphs examples are launching fine from the install location. Other examples fail to launch due:
/home/qt/RTA/Qt_6.10.0/example_install/examples/widgetvolumetric: error while loading shared libraries: libQt6GraphsWidgets.so.6: cannot open shared object file: No such file or directory

Only RHEL9.2 and SLES15_5 affected, launch works on Ubuntu22.04 x64 and Ubuntu24.04 arm64.