tmux mouse scroll

I keep running into this issue, as tmux changed it's mouse behaviour. To make it work again, add the following code snippet into your ~/.tmux.conf

set -g mouse on
bind -n WheelUpPane if-shell -F -t = "#{mouse_any_flag}" "send-keys -M" "if -Ft= '#{pane_in_mode}' 'send-keys -M' 'select-pane -t=; copy-mode -e; send-keys -M'"
bind -n WheelDownPane select-pane -t= \; send-keys -M

and reload the changed tmux configuration

$ tmux source ~/.tmux.conf