platform.assumeNotConscrypt()
    val tlsFallbackScsv = "TLS_FALLBACK_SCSV"
    val supportedCiphers = listOf(*handshakeCertificates.sslSocketFactory().supportedCipherSuites)
    if (!supportedCiphers.contains(tlsFallbackScsv)) {
      // This only works if the client socket supports TLS_FALLBACK_SCSV.
      return
    }
    server.useHttps(handshakeCertificates.sslSocketFactory())

    server.protocolNegotiationEnabled = true
    server.protocols = client.protocols
  }

  /**
   * Used during tests that involve TLS connection fallback attempts. OkHttp includes the
   * TLS_FALLBACK_SCSV cipher on fallback connections. See [FallbackTestClientSocketFactory]
   * for details.
   */