Tmux is a great terminal emulator!
Did you ever wanted to edit a file and got an error message telling you that another instance of the editor has the same file open?
Did you have to look everywhere for the editor?
Did you have multiple panes, windows, sessions where the editor could have been running? Was the editor running in a detached session?
tmux-ls displays a set of information about tmux sessions; the set contains sessions, windows and panes; which process is run in the pane and what files the process has opened. a set of options let you control what is displayed.
tmux-ls --help for all options.
tmux-ls displays extra information about the side-panes.
Copy tmux-ls somewhere in your path, read the documentation.