add: if ( !gDragDropEnabled ) return;  
context:   function DragOverPersonalToolbar ( event )  {    var validFlavor = false;    var dragSession = null;    var dragService = Components.classes["component://netscape/widget/dragservice"].getService();    if ( dragService ) dragService = dragService.QueryInterface(Components.interfaces.nsIDragService);    if ( dragService ) {      dragSession = dragService.getCurrentSession();      if ( dragSession ) {        if ( dragSession.isDataFlavorSupported("moz/toolbaritem") )          validFlavor = true;        else if ( dragSession.isDataFlavorSupported("text/plain") )          validFlavor = true;        //XXX other flavors here...        // touch the attribute to trigger the repaint with the drop feedback.        if ( validFlavor ) {          //XXX this is really slow and likes to refresh N times per second.          var toolbar = document.getElementById("PersonalToolbar");          toolbar.setAttribute ( "dd-triggerrepaint", 0 );          dragSession.canDrop = true;          event.preventBubble();        }      }    }  } // DragOverPersonalToolbar
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/2c86922f1c8008354485171557c1ef683b2002d4/navigator.js/clean/suite/browser/navigator.js