Long: proxy-tls13-ciphers Arg: help: TLS 1.3 proxy cipher suites Protocols: TLS --- Specifies which cipher suites to use in the connection to your HTTPS proxy when it negotiates TLS 1.3. The list of ciphers suites must specify valid ciphers. Read up on TLS 1.3 cipher suite details on this URL: https://curl.haxx.se/docs/ssl-ciphers.html If this option is used several times, the last one will be used.