--- a/browser/modules/PermissionUI.jsm
+++ b/browser/modules/PermissionUI.jsm
@@ -128,18 +128,19 @@ this.PermissionPromptPrototype = {
     return undefined;
   },
 
   /**
    * These are the options that will be passed to the
    * PopupNotification when it is shown. See the documentation
    * for PopupNotification for more details.
    *
-   * Note that prompt()  will automatically set displayURI to
-   * be the URI of the requesting pricipal.
+   * Note that prompt() will automatically set displayURI to
+   * be the URI of the requesting pricipal, unless the displayURI is exactly
+   * set to false.
    */
   get popupOptions() {
     return {};
   },
 
   /**
    * PopupNotification requires a unique ID to open the notification.
    * You must return a unique ID string here, for which PopupNotification
@@ -324,17 +325,20 @@ this.PermissionPromptPrototype = {
       popupNotificationActions.push(action);
     }
 
     let mainAction = popupNotificationActions.length ?
                      popupNotificationActions[0] : null;
     let secondaryActions = popupNotificationActions.splice(1);
 
     let options = this.popupOptions;
-    options.displayURI = this.principal.URI;
+
+    if (!options.hasOwnProperty('displayURI') || options.displayURI) {
+      options.displayURI = this.principal.URI;
+    }
 
     this.onBeforeShow();
     chromeWin.PopupNotifications.show(this.browser,
                                       this.notificationID,
                                       this.message,
                                       this.anchorID,
                                       mainAction,
                                       secondaryActions,