--- a/browser/base/content/newtab/page.js
+++ b/browser/base/content/newtab/page.js
@@ -82,20 +82,21 @@ let gPage = {
       this.updateModifiedFlag();
 
       // Initialize and render the grid.
       gGrid.init(this._gridSelector);
 
       // Initialize the drop target shim.
       gDropTargetShim.init();
 
+#ifdef XP_MACOSX
       // Workaround to prevent a delay on MacOSX due to a slow drop animation.
-      let doc = document.documentElement;
-      doc.addEventListener("dragover", this.onDragOver, false);
-      doc.addEventListener("drop", this.onDrop, false);
+      document.addEventListener("dragover", this.onDragOver, false);
+      document.addEventListener("drop", this.onDrop, false);
+#endif
     }.bind(this));
   },
 
   /**
    * Updates the 'page-disabled' attributes of the respective DOM nodes.
    * @param aValue Whether to set or remove attributes.
    */
   _updateAttributes: function Page_updateAttributes(aValue) {
@@ -150,24 +151,24 @@ let gPage = {
   },
 
   /**
    * Handles the 'dragover' event. Workaround to prevent a delay on MacOSX
    * due to a slow drop animation.
    * @param aEvent The 'dragover' event.
    */
   onDragOver: function Page_onDragOver(aEvent) {
-    if (gDrag.isValid(aEvent))
+    if (gDrag.isValid(aEvent) && gDrag.draggedSite)
       aEvent.preventDefault();
   },
 
   /**
    * Handles the 'drop' event. Workaround to prevent a delay on MacOSX due to
    * a slow drop animation.
    * @param aEvent The 'drop' event.
    */
   onDrop: function Page_onDrop(aEvent) {
-    if (gDrag.isValid(aEvent)) {
+    if (gDrag.isValid(aEvent) && gDrag.draggedSite) {
       aEvent.preventDefault();
       aEvent.stopPropagation();
     }
   }
 };