Long: tlsv1.3 Help: Use TLSv1.3 or greater Protocols: TLS Added: 7.52.0 --- Forces curl to use TLS version 1.3 or later when connecting to a remote TLS server. Note that TLS 1.3 is only supported by a subset of TLS backends. At the time of this writing, they are BoringSSL, NSS, and Secure Transport (on iOS 11 or later, and macOS 10.13 or later).