/usr/include/x86_64-linux-gnu/qt5/QtWaylandCompositor/QWaylandXdgShellV5 is in libqt5waylandcompositor5-dev 5.9.5-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 | #include "qwaylandxdgshellv5.h"
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