Try a different Role ? You are probably running the default "Essentials" role if you haven't changed.
See picture.
Or if you desire to modify the current role, RMB somewhere on the icons, - customize.. commands tab, scroll the left pane to find insert - curve from curves, pick extract from right pane and drag drop into/onto the place in the main menu system where you want it. Then RMB in the "whitespace" besides other roles "New User Role"