anchor.diff:      (values history-list current-index)))
   
   (defmethod load-webkit-history-entry ((buffer gtk-buffer) history-entry)
  +  (setf *loading-webkit-history-p* t)
     (webkit:webkit-web-view-go-to-back-forward-list-item
      (gtk-object buffer)
      (webkit-history-entry-gtk-object history-entry)))
  
positive.code:     (delete-buffer :id (id buffer)))
    (connect-signal buffer "load-failed" nil (web-view load-event failing-url error)
      (declare (ignore load-event web-view error))
      (unless (member (slot-value buffer 'load-status) '(:finished :failed))
        (echo "Failed to load URL ~a in buffer ~a." failing-url (id buffer))
        (setf (slot-value buffer 'load-status) :failed)
        (html-set
         (spinneret:with-html-string
          (:h1 "Page could not be loaded.")
          (:h2 "URL: " failing-url)
          (:ul
           (:li "Try again in a moment, maybe the site will be available again.")
           (:li "If the problem persists for every site, check your Internet connection.")
           (:li "Make sure the URL is valid."
                (when (quri:uri-https-p (quri:uri failing-url))
                  "If this site does not support HTTPS, try with HTTP (insecure)."))))
         buffer))
      t)
    (connect-signal buffer "create" nil (web-view navigation-action)
      (declare (ignore web-view))
  
negative.code:             (webkit:webkit-policy-decision-ignore response-policy-decision)
              nil)))))
  
  (defvar *loading-webkit-history-p* nil
    "Internal hack, do not use!")
  
  (define-ffi-method on-signal-load-changed ((buffer gtk-buffer) load-event)
    ;; `url' can be nil if buffer didn't have any URL associated
    ;; to the web view, e.g. the start page, or if the load failed.
  