This mod adds a few esssential binaries to NZBGet container.
ffmpeg openssl p7zip unzip unrar python2 par2
In NZBGet docker arguments, set an environment variable DOCKER_MODS=linuxserver/mods:nzbget-essentials
If adding multiple mods, enter them in an array separated by |, such as DOCKER_MODS=linuxserver/mods:nzbget-essentials|linuxserver/mods:nzbget-mod2