@VisibleForTesting
    void stripXFFHeaders(HttpRequest req) {
        HttpHeaders headers = req.headers();
        for (AsciiString headerName : HEADERS_TO_STRIP) {
            headers.remove(headerName);
        }
    }
@Test
    void strip_match() {
        StripUntrustedProxyHeadersHandler stripHandler = getHandler(AllowWhen.MUTUAL_SSL_AUTH);

        headers.add("x-forwarded-for", "abcd");
        stripHandler.stripXFFHeaders(msg);

        assertFalse(headers.contains("x-forwarded-for"));
    }