Install libnetfilter-conntrack-dev by entering the following commands in the terminal:
sudo apt update sudo apt install libnetfilter-conntrack-dev
Description:
Development files for libnetfilter-conntrack3
libnetfilter_conntrack is a userspace library providing a programming interface (API) to the in-kernel connection tracking state table. . This package provides development files and static libraries.
Homepage: http://www.netfilter.org/projects/libnetfilter_conntrack/
Version: 1.0.6-2
Section: libdevel