RscDisplayInventory could not detect the mouse third/forth/fifth (and so on...) button. It can only detect the left (0) and right (1) button.
Since we cannot override the right_button-to-drop_item issue in RscDisplayInventory, then we need other buttons to mess with.
"LBDblClick" is working fine, but it is unnatural for bringing up the sub menu contexts (DayZ-liked).