anchor.diff:          world-name)))))
   
   (defmethod ffi-buffer-evaluate-javascript-async ((buffer gtk-buffer) javascript &optional world-name)
  -  (when (gtk-object buffer)
  -    (%within-renderer-thread-async
  -    (lambda ()
  -      (webkit2:webkit-web-view-evaluate-javascript
  -       (gtk-object buffer)
  -       javascript
  -       nil
  -       #'javascript-error-handler
  -       world-name)))))
  +  (%within-renderer-thread-async
  +   (lambda ()
  +     (when (gtk-object buffer)
  +       (webkit2:webkit-web-view-evaluate-javascript
  +        (gtk-object buffer)
  +        javascript
  +        nil
  +        #'javascript-error-handler
  +        world-name)))))
   
   (define-ffi-method ffi-buffer-enable-javascript ((buffer gtk-buffer) value)
     (setf (webkit:webkit-settings-enable-javascript
  
positive.code:             (lambda (result jsc-result)
                (declare (ignore jsc-result))
                (calispel:! channel result))
              (lambda (result jsc-result)
                (declare (ignore jsc-result))
                result))
          (lambda (condition)
            (javascript-error-handler condition)
            ;; Notify the listener that we are done.
  
negative.code:         (webkit:webkit-web-view-load-uri (gtk-object buffer) (quri:render-uri url)))))
  
  (defmethod ffi-buffer-evaluate-javascript ((buffer gtk-buffer) javascript &optional world-name)
    (%within-renderer-thread
     (lambda (&optional channel)
       (when (gtk-object buffer)
         (webkit2:webkit-web-view-evaluate-javascript
          (gtk-object buffer)
          javascript
  