/usr/ is in libspectre-dev 0.2.7-2ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/
/usr/share/doc/
/usr/share/doc/libspectre-dev/
/usr/share/doc/libspectre-dev/copyright
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/libspectre.pc
/usr/lib/x86_64-linux-gnu/libspectre.a
/usr/include/
/usr/include/libspectre/
/usr/include/libspectre/spectre-render-context.h
/usr/include/libspectre/spectre-document.h
/usr/include/libspectre/spectre-page.h
/usr/include/libspectre/spectre-version.h
/usr/include/libspectre/spectre.h
/usr/include/libspectre/spectre-exporter.h
/usr/include/libspectre/spectre-macros.h
/usr/include/libspectre/spectre-status.h
/usr/share/doc/libspectre-dev/changelog.Debian.gz
/usr/lib/x86_64-linux-gnu/libspectre.so