/usr/ is in libnetfilter-conntrack-dev 1.0.6-2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/
/usr/include/libnetfilter_conntrack/
/usr/include/libnetfilter_conntrack/libnetfilter_conntrack.h
/usr/include/libnetfilter_conntrack/libnetfilter_conntrack_dccp.h
/usr/include/libnetfilter_conntrack/libnetfilter_conntrack_icmp.h
/usr/include/libnetfilter_conntrack/libnetfilter_conntrack_ipv4.h
/usr/include/libnetfilter_conntrack/libnetfilter_conntrack_ipv6.h
/usr/include/libnetfilter_conntrack/libnetfilter_conntrack_sctp.h
/usr/include/libnetfilter_conntrack/libnetfilter_conntrack_tcp.h
/usr/include/libnetfilter_conntrack/libnetfilter_conntrack_udp.h
/usr/include/libnetfilter_conntrack/linux_nfnetlink_conntrack.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/libnetfilter_conntrack.pc
/usr/share/
/usr/share/doc/
/usr/lib/x86_64-linux-gnu/libnetfilter_conntrack.so
/usr/share/doc/libnetfilter-conntrack-dev