/usr/include/KF5/KIOFileWidgets/ is in kio-dev 5.18.0-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/KF5/KIOFileWidgets/KAbstractViewAdapter
/usr/include/KF5/KIOFileWidgets/KDirOperator
/usr/include/KF5/KIOFileWidgets/KDirSortFilterProxyModel
/usr/include/KF5/KIOFileWidgets/KEncodingFileDialog
/usr/include/KF5/KIOFileWidgets/KFileCopyToMenu
/usr/include/KF5/KIOFileWidgets/KFileFilterCombo
/usr/include/KF5/KIOFileWidgets/KFilePlacesModel
/usr/include/KF5/KIOFileWidgets/KFilePlacesView
/usr/include/KF5/KIOFileWidgets/KFilePreviewGenerator
/usr/include/KF5/KIOFileWidgets/KFileWidget
/usr/include/KF5/KIOFileWidgets/KImageFilePreview
/usr/include/KF5/KIOFileWidgets/KNameAndUrlInputDialog
/usr/include/KF5/KIOFileWidgets/KNewFileMenu
/usr/include/KF5/KIOFileWidgets/KPreviewWidgetBase
/usr/include/KF5/KIOFileWidgets/KRecentDirs
/usr/include/KF5/KIOFileWidgets/KStatusBarOfflineIndicator
/usr/include/KF5/KIOFileWidgets/KUrlNavigator
/usr/include/KF5/KIOFileWidgets/kabstractviewadapter.h
/usr/include/KF5/KIOFileWidgets/kdiroperator.h
/usr/include/KF5/KIOFileWidgets/kdirsortfilterproxymodel.h
/usr/include/KF5/KIOFileWidgets/kencodingfiledialog.h
/usr/include/KF5/KIOFileWidgets/kfilecopytomenu.h
/usr/include/KF5/KIOFileWidgets/kfilefiltercombo.h
/usr/include/KF5/KIOFileWidgets/kfileplacesmodel.h
/usr/include/KF5/KIOFileWidgets/kfileplacesview.h
/usr/include/KF5/KIOFileWidgets/kfilepreviewgenerator.h
/usr/include/KF5/KIOFileWidgets/kfilewidget.h
/usr/include/KF5/KIOFileWidgets/kimagefilepreview.h
/usr/include/KF5/KIOFileWidgets/kiofilewidgets_export.h
/usr/include/KF5/KIOFileWidgets/knameandurlinputdialog.h
/usr/include/KF5/KIOFileWidgets/knewfilemenu.h
/usr/include/KF5/KIOFileWidgets/kpreviewwidgetbase.h
/usr/include/KF5/KIOFileWidgets/krecentdirs.h
/usr/include/KF5/KIOFileWidgets/kstatusbarofflineindicator.h
/usr/include/KF5/KIOFileWidgets/kurlnavigator.h