code: private static void quietParseUnrecognizedElement(final Object instance,
                                            final Element element,
                                            final Properties props) {
        try {
            parseUnrecognizedElement(instance, element, props);
        } catch (Exception ex) {
            LogLog.error("Error in extension content: ", ex);
        }
    }
docs: Delegates unrecognized content to created instance if
  it supports UnrecognizedElementParser and catches and
  logs any exception.
  @since 1.2.15
  @param instance instance, may be null.
  @param element element, may not be null.
  @param props properties