Enable environment variables update on tmux

tmux.conf

@@ -27,6 +27,7 @@ set-window-option -g window-status-bell-fg red
 set-window-option -g window-status-activity-bg green
 set-window-option -g window-status-activity-fg black
 set-window-option -g utf8 on
+set-window-option -g xterm-keys on
 
 # Statusbar
 set -g status-bg black
@@ -38,17 +39,14 @@ set-option -g mouse-select-pane off
 set-option -g status-keys vi
 set-option -g set-titles on
 set-option -g status-utf8 on
-# window number,program name,active (or not)
-#set-option -g set-titles-string '#H:#S.#I.#P #W #T'
 
 setw -g mode-keys vi
 setw -g mode-mouse off
 setw -g monitor-activity on
 
 set -g history-limit 4096
-
 set -g base-index 1
-
 set -s escape-time 0
+set -g update-environment -r
 
 bind r source-file ~/.tmux.conf