(define-key gametree-mode-map [M-down-mouse-2 M-mouse-2]
'gametree-mouse-break-line-here)
(define-key gametree-mode-map [S-down-mouse-1 S-mouse-1]
(define-key gametree-mode-map [M-down-mouse-2 M-mouse-2]
'gametree-mouse-break-line-here)
(define-key gametree-mode-map [S-down-mouse-1 S-mouse-1]