/usr/include/KF5/KWayland/Client/ is in libkf5wayland-dev 4:5.44.0-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/KF5/KWayland/Client/appmenu.h
/usr/include/KF5/KWayland/Client/blur.h
/usr/include/KF5/KWayland/Client/buffer.h
/usr/include/KF5/KWayland/Client/compositor.h
/usr/include/KF5/KWayland/Client/connection_thread.h
/usr/include/KF5/KWayland/Client/contrast.h
/usr/include/KF5/KWayland/Client/datadevice.h
/usr/include/KF5/KWayland/Client/datadevicemanager.h
/usr/include/KF5/KWayland/Client/dataoffer.h
/usr/include/KF5/KWayland/Client/datasource.h
/usr/include/KF5/KWayland/Client/dpms.h
/usr/include/KF5/KWayland/Client/event_queue.h
/usr/include/KF5/KWayland/Client/fakeinput.h
/usr/include/KF5/KWayland/Client/fullscreen_shell.h
/usr/include/KF5/KWayland/Client/idle.h
/usr/include/KF5/KWayland/Client/idleinhibit.h
/usr/include/KF5/KWayland/Client/keyboard.h
/usr/include/KF5/KWayland/Client/kwaylandclient_export.h
/usr/include/KF5/KWayland/Client/output.h
/usr/include/KF5/KWayland/Client/outputconfiguration.h
/usr/include/KF5/KWayland/Client/outputdevice.h
/usr/include/KF5/KWayland/Client/outputmanagement.h
/usr/include/KF5/KWayland/Client/plasmashell.h
/usr/include/KF5/KWayland/Client/plasmawindowmanagement.h
/usr/include/KF5/KWayland/Client/plasmawindowmodel.h
/usr/include/KF5/KWayland/Client/pointer.h
/usr/include/KF5/KWayland/Client/pointerconstraints.h
/usr/include/KF5/KWayland/Client/pointergestures.h
/usr/include/KF5/KWayland/Client/region.h
/usr/include/KF5/KWayland/Client/registry.h
/usr/include/KF5/KWayland/Client/relativepointer.h
/usr/include/KF5/KWayland/Client/seat.h
/usr/include/KF5/KWayland/Client/server_decoration.h
/usr/include/KF5/KWayland/Client/server_decoration_palette.h
/usr/include/KF5/KWayland/Client/shadow.h
/usr/include/KF5/KWayland/Client/shell.h
/usr/include/KF5/KWayland/Client/shm_pool.h
/usr/include/KF5/KWayland/Client/slide.h
/usr/include/KF5/KWayland/Client/subcompositor.h
/usr/include/KF5/KWayland/Client/subsurface.h
/usr/include/KF5/KWayland/Client/surface.h
/usr/include/KF5/KWayland/Client/textinput.h
/usr/include/KF5/KWayland/Client/touch.h
/usr/include/KF5/KWayland/Client/xdgforeign_v2.h
/usr/include/KF5/KWayland/Client/xdgshell.h