tmux - 2.8-3+deb10u1 main

tmux enables a number of terminals (or windows) to be accessed and
controlled from a single terminal like screen. tmux runs as a
server-client system. A server is created automatically when necessary
and holds a number of sessions, each of which may have a number of
windows linked to it. Any number of clients may connect to a session,
or the server may be controlled by issuing commands with tmux.
Communication takes place through a socket, by default placed in /tmp.
Moreover tmux provides a consistent and well-documented command
interface, with the same syntax whether used interactively, as a key
binding, or from the shell. It offers a choice of vim or Emacs key
layouts.