diff --git a/include/proto/connection.h b/include/proto/connection.h
index 47825a0..1aa0ed9 100644
--- a/include/proto/connection.h
+++ b/include/proto/connection.h
@@ -971,7 +971,14 @@
 		struct ist mux_proto;
 		const char *alpn_str = NULL;
 		int alpn_len = 0;
-		int mode = (1 << (bind_conf->frontend->mode == PR_MODE_HTTP));
+		int mode;
+
+		if (bind_conf->frontend->mode == PR_MODE_TCP)
+			mode = PROTO_MODE_TCP;
+		else if (bind_conf->frontend->options2 & PR_O2_USE_HTX)
+			mode = PROTO_MODE_HTX;
+		else
+			mode = PROTO_MODE_HTTP;
 
 		conn_get_alpn(conn, &alpn_str, &alpn_len);
 		mux_proto = ist2(alpn_str, alpn_len);
@@ -1003,7 +1010,13 @@
 	else {
 		int mode;
 
-		mode = (1 << (prx->mode == PR_MODE_HTTP));
+		if (prx->mode == PR_MODE_TCP)
+			mode = PROTO_MODE_TCP;
+		else if (prx->options2 & PR_O2_USE_HTX)
+			mode = PROTO_MODE_HTX;
+		else
+			mode = PROTO_MODE_HTTP;
+
 		mux_ops = conn_get_best_mux(conn, ist(NULL), PROTO_SIDE_BE, mode);
 		if (!mux_ops)
 			return -1;
diff --git a/include/types/connection.h b/include/types/connection.h
index 827df36..889decb 100644
--- a/include/types/connection.h
+++ b/include/types/connection.h
@@ -425,7 +425,8 @@
 	PROTO_MODE_NONE = 0,
 	PROTO_MODE_TCP  = 1 << 0, // must not be changed!
 	PROTO_MODE_HTTP = 1 << 1, // must not be changed!
-	PROTO_MODE_ANY  = PROTO_MODE_TCP | PROTO_MODE_HTTP,
+	PROTO_MODE_HTX  = 1 << 2, // must not be changed!
+	PROTO_MODE_ANY  = PROTO_MODE_TCP | PROTO_MODE_HTTP, // note: HTX is experimental and must not appear here
 };
 
 enum proto_proxy_side {
diff --git a/include/types/proxy.h b/include/types/proxy.h
index b5f5b9b..da09848 100644
--- a/include/types/proxy.h
+++ b/include/types/proxy.h
@@ -151,7 +151,7 @@
 #define PR_O2_SRC_ADDR	0x00100000	/* get the source ip and port for logs */
 
 #define PR_O2_FAKE_KA   0x00200000      /* pretend we do keep-alive with server eventhough we close */
-/* unused: 0x00400000 */
+#define PR_O2_USE_HTX   0x00400000      /* use the HTX representation for the HTTP protocol */
 #define PR_O2_EXP_NONE  0x00000000      /* http-check : no expect rule */
 #define PR_O2_EXP_STS   0x00800000      /* http-check expect status */
 #define PR_O2_EXP_RSTS  0x01000000      /* http-check expect rstatus */