Macro last_window

macro_rules! last_window {
    (@cmd ($cmd:expr) -t $target_session:expr, $($tail:tt)*) => { ... };
    (@cmd ($cmd:expr)) => { ... };
    () => { ... };
    (($cmd:expr), $($tail:tt)*) => { ... };
    ($($tail:tt)*) => { ... };
}

Select the last (previously selected) window

Manual

tmux ^0.8:

last-window [-t target-session]
(alias: last)