Copy selection
copy mode
// what it does
In vi copy mode, Enter runs `copy-pipe-and-cancel`, which (with no pipe command) copies the highlighted text into tmux's most recent paste buffer and exits copy mode in one step. It's the normal way to finish a copy once you've marked a region with Space.
// shortcut
Enter
// gotcha
This writes to a tmux paste buffer, not your system clipboard — the text won't reach other apps unless you enable `set -g set-clipboard on` (with an OSC 52-capable terminal) or rebind the key to copy-pipe through pbcopy/xclip.