LuLu is a free open source firewall for macOS, capable of alerting and blocking unwanted connections.
Netiquette is a open-source tool used to monitor network connections via GUI as well as CLI for macOS
TextSniper enables you to effortlessly extract non-selectable text from a wide range of sources, including YouTube videos, PDFs, images, online courses, and beyond, all in an instant.
TaskExplorer is a free open-source software enabling users to view running processes signatures, network connections, etc. on macOS.