/usr/include/x86_64-linux-gnu/ is in qtquickcontrols2-5-dev 5.7.1-1.
This file is owned by root:root, with mode 0o755.
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/usr/include/x86_64-linux-gnu/qt5/
/usr/include/x86_64-linux-gnu/qt5/QtQuickControls2/
/usr/include/x86_64-linux-gnu/qt5/QtQuickControls2/QQuickStyle
/usr/include/x86_64-linux-gnu/qt5/QtQuickControls2/QtQuickControls2
/usr/include/x86_64-linux-gnu/qt5/QtQuickControls2/QtQuickControls2Depends
/usr/include/x86_64-linux-gnu/qt5/QtQuickControls2/QtQuickControls2Version
/usr/include/x86_64-linux-gnu/qt5/QtQuickControls2/qquickstyle.h
/usr/include/x86_64-linux-gnu/qt5/QtQuickControls2/qtquickcontrols2global.h
/usr/include/x86_64-linux-gnu/qt5/QtQuickControls2/qtquickcontrols2version.h
/usr/include/x86_64-linux-gnu/qt5/QtQuickTemplates2/
/usr/include/x86_64-linux-gnu/qt5/QtQuickTemplates2/QtQuickTemplates2
/usr/include/x86_64-linux-gnu/qt5/QtQuickTemplates2/QtQuickTemplates2Depends
/usr/include/x86_64-linux-gnu/qt5/QtQuickTemplates2/QtQuickTemplates2Version
/usr/include/x86_64-linux-gnu/qt5/QtQuickTemplates2/qtquicktemplates2version.h