The tmux-terminal commands typically run
tmux split-window kak -c ${kak_session} </dev/null >/dev/null 2>&1 &
The tmux process runs in the background with output silenced. This is
not necessary because "tmux split-window" is a thin client that
merely forwards its arguments to the tmux server. All our wrappers
for other terminal-servers (kitty, iterm, screen, wezterm, zellij)
simply run in the foreground, not silencing any errors.
The tmux backgrounding was added in 208b91627 (Move client.kak as
x11.kak and change tmux.kak to be its peer, 2015-11-17), probably for
consistency with x11.kak. That one is different however because it
potentially spawns a full terminal, not just a client that briefly
talks to a terminal server - that's why x11-terminal needs to use
"setsid," to avoid killing said terminal when we signal our process
group.
Remove the backgrounding from tmux.kak for consistency and to reduce
surprise.
f26d4ea4bf