static boolean isJSFStatefulForm(@NonNull String savedFormData) {
        var matcher = VIEW_STATE_PATTERN.matcher(savedFormData);
        return matcher.find() && matcher.groupCount() >= 2
                && !matcher.group(2).equalsIgnoreCase("stateless");
    }
flash cookie is preserved here

@param request
@param response
@param path
@param paramValues
support/jakarta-ee/src/main/java/org/apache/shiro/ee/filters/FormResubmitSupport.java