Port Manager Extension

The Port manager extension lists open ports and allows to kill the processes which open them. It allows killing either with the default SIGTERM signal or SIGKILL, which can't be ignored by the process.

It also offers the ability to copy information about the process (PID, Name, Parent PID, User name, User UID) or a kill command to paste in a terminal.

Use Sudo

The settings provide the option to run Isof and kill commands with sudo (as root), which is deactivated by default. Before activating the option, make sure your user is set up for passwordless use of the sudo command. However, if you don't already know what this means or how to do it, you probably shouldn't do it. Doing it poses an considerable security risk and (if done wrongly) might break your macOS installation. If you still wanna do it, make sure to use visudo. You have been warned.

Despite the aforementioned risks, I included the option because it adds an essential functionality: To see processes which are not owned by your own user.