diff --git a/doc/configuration.txt b/doc/configuration.txt
index b78981f..decfd3a 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -14101,6 +14101,8 @@
 
        server 127.0.0.1:443 ssl crt pub.pem alpn h2,http/1.1
 
+  See also "ws" to use an alternative ALPN for websocket streams.
+
 backup
   When "backup" is present on a server line, the server is only used in load
   balancing when all other non-backup servers are unavailable. Requests coming
@@ -14714,6 +14716,8 @@
   Idea behind this option is to bypass the selection of the best multiplexer's
   protocol for all connections established to this server.
 
+  See also "ws" to use an alternative protocol for websocket streams.
+
 redir <prefix>
   The "redir" parameter enables the redirection mode for all GET and HEAD
   requests addressing this server. This means that instead of having HAProxy
@@ -15046,6 +15050,26 @@
   can both grow and shrink, for instance between 10 and 100 to leave enough
   room above and below for later adjustments.
 
+ws { auto | h1 | h2 }
+  This option allows to configure the protocol used when relaying websocket
+  streams. This is most notably useful when using an HTTP/2 backend without the
+  support for H2 websockets through the RFC8441.
+
+  The default mode is "auto". This will reuse the same protocol as the main
+  one. The only difference is when using ALPN. In this case, it can try to
+  downgrade the ALPN to "http/1.1" only for websocket streams if the configured
+  server ALPN contains it.
+
+  The value "h1" is used to force HTTP/1.1 for websockets streams, through ALPN
+  if SSL ALPN is activated for the server. Similarly, "h2" can be used to
+  force HTTP/2.0 websockets. Use this value with care : the server must support
+  RFC8441 or an error will be reported by haproxy when relaying websockets.
+
+  Note that NPN is not taken into account as its usage has been deprecated in
+  favor of the ALPN extension.
+
+  See also "alpn" and "proto".
+
 
 5.3. Server IP address resolution using DNS
 -------------------------------------------