/usr/ is in libgtkspellmm-3.0-dev 3.0.3+dfsg-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/
/usr/include/gtkspellmm-3.0/
/usr/include/gtkspellmm-3.0/gtkspellmm.h
/usr/include/gtkspellmm-3.0/gtkspellmm/
/usr/include/gtkspellmm-3.0/gtkspellmm/private/
/usr/include/gtkspellmm-3.0/gtkspellmm/private/gtkspell_p.h
/usr/include/gtkspellmm-3.0/gtkspellmm/init.h
/usr/include/gtkspellmm-3.0/gtkspellmm/gtkspell.h
/usr/include/gtkspellmm-3.0/gtkspellmm/wrap_init.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/gtkspellmm-3.0.pc
/usr/lib/x86_64-linux-gnu/gtkspellmm-3.0/
/usr/lib/x86_64-linux-gnu/gtkspellmm-3.0/include/
/usr/lib/x86_64-linux-gnu/gtkspellmm-3.0/include/gtkspellmmconfig.h
/usr/share/
/usr/share/doc/
/usr/share/doc/libgtkspellmm-3.0-dev/
/usr/share/doc/libgtkspellmm-3.0-dev/changelog.Debian.gz
/usr/share/doc/libgtkspellmm-3.0-dev/changelog.gz
/usr/share/doc/libgtkspellmm-3.0-dev/copyright
/usr/lib/x86_64-linux-gnu/libgtkspellmm-3.0.so