nsIDOMWindowUtils
deprecated since gecko 38.0 key_flag_location_right 0x0040 location attrubute of the sending key event by sendkeyevent() returns keyboardevent.dom_key_location_right if this is specified to the aadditionalflags.

KeyboardEvent.location - Web APIs
dom_key_location_right 2 the key was the right-hand version of the key; for example, the right-hand control key is pressed on a standard 101 key us keyboard.

KeyboardEvent - Web APIs
dom_key_location_right 0x02 the key is one which may exist in multiple positions on the keyboard and, in this case, is located on the right side of the keyboard.