use vim keybindings in copy mode

tmux.conf

@@ -17,11 +17,16 @@ unbind C-b
 set -g prefix C-a
 bind C-a send-prefix
 
-# Copy-paste integration
+# Use vim keybindings in copy mode
 setw -g mode-keys vi
-bind -t vi-copy 'v' begin-selection
-bind -t vi-copy 'y' copy-selection
-bind y run-shell "tmux show-buffer | xclip -sel clip -i" \; display-message "Copied tmux buffer to system clipboard"
+
+# Setup 'v' to begin selection as in Vim
+bind-key -t vi-copy v begin-selection
+bind-key -t vi-copy y copy-pipe "reattach-to-user-namespace pbcopy"
+
+# Update default binding of `Enter` to also use copy-pipe
+unbind -t vi-copy Enter
+bind-key -t vi-copy Enter copy-pipe "reattach-to-user-namespace pbcopy"
 
 # splitting panes
 bind v split-window -h