tmux/session/Name

• Each tmux/session can have a name. by default this appears in the leftmost part of the tmux/Status Line
  • Only the first nine characters of it appear there, because tmux/Option/status-left-length defaults to 10 and the bracket in tmux/Option/status-left takes one column.
  • A name with a dot in it cannot be targeted. -t parses session:window.pane, so a dot is read as a separator and every bare target — has-session among them — resolves against a window or pane that is not there: tmux/Q/Why does a session name containing a dot break every bare -t target?.