zsh/widgets/edit-command-line-split

edit-command-line-tmux() {
	local tmpfile=${TMPPREFIX:-/tmp/zsh}ecl$$

	print -R - "$PREBUFFER$BUFFER" >$tmpfile
	exec </dev/tty
	if [[ $KITTY_WINDOW_ID ]]; then
		kitty @launch --type overlay vim -c 'set laststatus=0 showtabline=0 ft=zsh' $tmpfile
		tail -f --pid=$(pgrep -f "vim.*${tmpfile:t}") /dev/null
	else
		${=${VISUAL:-${EDITOR:-vi}}} $tmpfile
	fi
	print -Rz - "$(<$tmpfile)" 

	command rm -f $tmpfile
	zle send-break		# Force reload from the buffer stack
}