I tried the first answer without success.
I was able to get the results I wanted by doing the following:
tmux attach
I entered tmux and saw the other session was still attached
So I detached my current session to get back to a shell: CTRL+B D
Then I issued the following:
tmux attach -d
This says to attach to the default session, and detach all other sessions currently attached. See the man page under Clients and Sessions
attach-session [-dr] [-t target-session]
(alias: attach)
If run from outside tmux, create a new client in the current terminal and attach it to
target-session. If used from inside, switch the current client. If -d is specified, any other
clients attached to the session are detached. -r signifies the client is read-only (only keys bound
to the detach-client command have any effect)
tmux detach
, it doesn't require a keyboard since it's a command.C-b d
is good to detach in the normal fashion, only 1 tmux session going on. C is usually Clt.