The answer is, it depends. If you copy it with the mouse, you will be copying both sides. If you copy it with your tmux keyboard copy bindings, it will copy jus

The answer is, it depends. If you copy it with the mouse, you will be copying both sides. If you copy it with your tmux keyboard copy bindings, it will copy just the one side. I don't know the default bindings because I made mine prefix-esc to get to copy mode, vi keys, v to select, y to yank.