@Override
        public void onLoadError(CefBrowser browser, CefFrame frame, ErrorCode errorCode, String errorText, String failedUrl) {
          // do not show error page if another URL has already been requested to load
          ErrorPage errorPage = myErrorPage;
          String lastRequestedUrl = getLastRequestedUrl();
          if (errorPage != null && lastRequestedUrl.equals(failedUrl)) {
            String html = errorPage.create(errorCode, errorText, failedUrl);
            if (html != null) UIUtil.invokeLaterIfNeeded(() -> compareLastRequestedUrlAndPerform(failedUrl, () -> loadHTML(html)));
          }
        }
@Override
        public void onLoadError(CefBrowser browser, CefFrame frame, ErrorCode errorCode, String errorText, String failedUrl)