+ // Add relatedTarget, if necessary
+ if ( !event.relatedTarget && event.fromElement )
+ event.relatedTarget = event.fromElement == event.target ? event.toElement : event.fromElement;
+
+ // Add metaKey to non-Mac browsers (use ctrl for PC's and Meta for Macs)
+ if ( event.metaKey == null && event.ctrlKey != null )
+ event.metaKey = event.ctrlKey;
+
+ // Add which for click: 1 == left; 2 == middle; 3 == right
+ // Note: button is not normalized, so don't use it
+ if ( event.which == null && event.button != null )
+ event.which = (event.button & 1 ? 1 : ( event.button & 2 ? 3 : ( event.button & 4 ? 2 : 0 ) ));
+