diff --git a/src/plugins/relay/relay-http.c b/src/plugins/relay/relay-http.c
index 6a522e534..8cde856b9 100644
--- a/src/plugins/relay/relay-http.c
+++ b/src/plugins/relay/relay-http.c
@@ -560,15 +560,18 @@ relay_http_add_to_body (struct t_relay_http_request *request,
 int
 relay_http_get_auth_status (struct t_relay_client *client)
 {
-    const char *auth, *client_totp, *pos;
+    const char *auth, *sec_websocket_protocol, *client_totp, *pos;
     char *relay_password, *totp_secret, *info_totp_args, *info_totp;
     char *user_pass;
-    int rc, length, totp_ok;
+    char **protocol_array;
+    int rc, i, length, protocol_count, use_base64url, totp_ok;
 
     rc = 0;
     relay_password = NULL;
+    protocol_array = NULL;
     totp_secret = NULL;
     user_pass = NULL;
+    use_base64url = 0;
 
     relay_password = weechat_string_eval_expression (
         weechat_config_string (relay_config_network_password),
@@ -589,13 +592,43 @@ relay_http_get_auth_status (struct t_relay_client *client)
     if (relay_password[0])
     {
         auth = weechat_hashtable_get (client->http_req->headers, "authorization");
-        if (!auth || (weechat_strncasecmp (auth, "basic ", 6) != 0))
+
+        if (auth)
         {
-            rc = -1;
-            goto end;
+            if (weechat_strncasecmp (auth, "basic ", 6) != 0)
+            {
+                rc = -1;
+                goto end;
+            }
+
+            pos = auth + 6;
+        }
+        else
+        {
+            sec_websocket_protocol = weechat_hashtable_get (
+                client->http_req->headers, "sec-websocket-protocol");
+            protocol_array = weechat_string_split (sec_websocket_protocol,
+                                                   ",", " ", 0, 0, &protocol_count);
+
+            pos = NULL;
+            for (i = 0; i < protocol_count; i++)
+            {
+                if (strncmp (protocol_array[i],
+                             "base64url.bearer.authorization.weechat.", 39) == 0)
+                {
+                    pos = protocol_array[i] + 39;
+                    use_base64url = 1;
+                    break;
+                }
+            }
+
+            if (!pos)
+            {
+                rc = -1;
+                goto end;
+            }
         }
 
-        pos = auth + 6;
         while (pos[0] == ' ')
         {
             pos++;
@@ -608,7 +641,8 @@ relay_http_get_auth_status (struct t_relay_client *client)
             rc = -8;
             goto end;
         }
-        length = weechat_string_base_decode ("64", pos, user_pass);
+        length = weechat_string_base_decode ((use_base64url) ? "64url" : "64",
+                                             pos, user_pass);
         if (length < 0)
         {
             rc = -2;
@@ -616,7 +650,9 @@ relay_http_get_auth_status (struct t_relay_client *client)
         }
         if (strncmp (user_pass, "plain:", 6) == 0)
         {
-            switch (relay_auth_check_password_plain (client, user_pass + 6, relay_password))
+            switch (relay_auth_check_password_plain (client,
+                                                     user_pass + 6,
+                                                     relay_password))
             {
                 case 0: /* password OK */
                     break;
@@ -631,7 +667,8 @@ relay_http_get_auth_status (struct t_relay_client *client)
         }
         else if (strncmp (user_pass, "hash:", 5) == 0)
         {
-            switch (relay_auth_password_hash (client, user_pass + 5, relay_password))
+            switch (relay_auth_password_hash (client, user_pass + 5,
+                                              relay_password))
             {
                 case 0: /* password OK */
                     break;
@@ -692,6 +729,7 @@ relay_http_get_auth_status (struct t_relay_client *client)
     }
 
 end:
+    weechat_string_free_split (protocol_array);
     free (relay_password);
     free (totp_secret);
     free (user_pass);
diff --git a/src/plugins/relay/relay-websocket.c b/src/plugins/relay/relay-websocket.c
index 330aac959..2bc023889 100644
--- a/src/plugins/relay/relay-websocket.c
+++ b/src/plugins/relay/relay-websocket.c
@@ -400,10 +400,12 @@ relay_websocket_parse_extensions (const char *extensions,
 char *
 relay_websocket_build_handshake (struct t_relay_http_request *request)
 {
-    const char *sec_websocket_key;
+    const char *sec_websocket_key, *sec_websocket_protocol_request;
     char *key, sec_websocket_accept[128], handshake[4096], hash[160 / 8];
-    char **extensions, str_window_bits[128], sec_websocket_extensions[1024];
-    int length, hash_size;
+    char **extensions, **protocol_array, str_window_bits[128];
+    char sec_websocket_extensions[1024];
+    char sec_websocket_protocol[1024];
+    int i, length, hash_size, protocol_count;
 
     if (!request)
         return NULL;
@@ -481,6 +483,24 @@ relay_websocket_build_handshake (struct t_relay_http_request *request)
         sec_websocket_extensions[0] = '\0';
     }
 
+    sec_websocket_protocol_request = weechat_hashtable_get (
+        request->headers, "sec-websocket-protocol");
+    protocol_array = weechat_string_split (sec_websocket_protocol_request,
+                                           ",", " ", 0, 0, &protocol_count);
+
+    sec_websocket_protocol[0] = '\0';
+    for (i = 0; i < protocol_count; i++)
+    {
+        if (strcmp (protocol_array[i], WEBSOCKET_SUB_PROTOCOL_API_WEECHAT) == 0)
+        {
+            snprintf (
+                sec_websocket_protocol, sizeof (sec_websocket_protocol),
+                "Sec-WebSocket-Protocol: %s\r\n",
+                WEBSOCKET_SUB_PROTOCOL_API_WEECHAT);
+            break;
+        }
+    }
+
     /* build the handshake (it will be sent as-is to client) */
     snprintf (handshake, sizeof (handshake),
               "HTTP/1.1 101 Switching Protocols\r\n"
@@ -488,9 +508,11 @@ relay_websocket_build_handshake (struct t_relay_http_request *request)
               "Connection: Upgrade\r\n"
               "Sec-WebSocket-Accept: %s\r\n"
               "%s"
+              "%s"
               "\r\n",
               sec_websocket_accept,
-              sec_websocket_extensions);
+              sec_websocket_extensions,
+              sec_websocket_protocol);
 
     return strdup (handshake);
 }
diff --git a/src/plugins/relay/relay-websocket.h b/src/plugins/relay/relay-websocket.h
index 5845a4e8f..e1d4071b8 100644
--- a/src/plugins/relay/relay-websocket.h
+++ b/src/plugins/relay/relay-websocket.h
@@ -37,6 +37,8 @@
 #define WEBSOCKET_FRAME_OPCODE_PING         0x09
 #define WEBSOCKET_FRAME_OPCODE_PONG         0x0A
 
+#define WEBSOCKET_SUB_PROTOCOL_API_WEECHAT "api.weechat"
+
 struct t_relay_client;
 struct t_relay_http_request;