/usr/include/KF5/ is in libkf5completion-dev 5.18.0-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/KF5/KCompletion/
/usr/include/KF5/KCompletion/KComboBox
/usr/include/KF5/KCompletion/KCompletion
/usr/include/KF5/KCompletion/KCompletionBase
/usr/include/KF5/KCompletion/KCompletionBox
/usr/include/KF5/KCompletion/KCompletionMatches
/usr/include/KF5/KCompletion/KHistoryComboBox
/usr/include/KF5/KCompletion/KLineEdit
/usr/include/KF5/KCompletion/KPixmapProvider
/usr/include/KF5/KCompletion/KSortableList
/usr/include/KF5/KCompletion/kcombobox.h
/usr/include/KF5/KCompletion/kcompletion.h
/usr/include/KF5/KCompletion/kcompletion_export.h
/usr/include/KF5/KCompletion/kcompletionbase.h
/usr/include/KF5/KCompletion/kcompletionbox.h
/usr/include/KF5/KCompletion/kcompletionmatches.h
/usr/include/KF5/KCompletion/khistorycombobox.h
/usr/include/KF5/KCompletion/klineedit.h
/usr/include/KF5/KCompletion/kpixmapprovider.h
/usr/include/KF5/KCompletion/ksortablelist.h
/usr/include/KF5/kcompletion_version.h