master-server/deps/curl/docs/cmdline-opts/no-npn.md

c	SPDX-License-Identifier	Long	Tags	Protocols	Added	Mutexed	Requires	Help	Category	Multi	See-also	Example
Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.	curl	no-npn	Versions HTTP/2	HTTPS	7.36.0		TLS	Disable the NPN TLS extension	tls http	boolean	no-alpn http2	--no-npn $URL

--no-npn

curl never uses NPN, this option has no effect (added in 7.86.0).

Disable the NPN TLS extension. NPN is enabled by default if libcurl was built with an SSL library that supports NPN. NPN is used by a libcurl that supports HTTP/2 to negotiate HTTP/2 support with the server during https sessions.