Depois de ler este artigo , aprendi sobre o novo copy-pipe
comando que foi adicionado ao tmux 1.8 :
copy-pipe
mode command to copy selection and pipe the selection to a command.
Alterar as ligações do modo de cópia para usar o novo comando copy-pipe
corrigiu o problema para mim:
# (from my tmux.conf)...
# Change copy / paste bindings to work like Vim
# Note this used to use 'copy-selection' but that has been replaced
# with 'copy-pipe' as of Tmux 1.8. See: https://goo.gl/ea3CRO
bind Escape copy-mode
bind p paste-buffer
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"