Comment by bluehavana

I don't seem to have that problem, :/

make sure "mouse-mode on" is set, rather than "mouse-mode copy-mode".

Here is my mouse config:

set-window-option -g mode-mouse on

set-option -g mouse-resize-pane on

set-option -g mouse-select-pane on

set-option -g mouse-select-window on

set-option -g mouse-utf8 on