diff --git a/libs/hbb_common b/libs/hbb_common
index 229b90450..5d52530b6 160000
--- a/libs/hbb_common
+++ b/libs/hbb_common
@@ -1 +1 @@
-Subproject commit 229b904508364c8997aad0fb5af57effac859f60
+Subproject commit 5d52530b636fb296a324260b074780cf559e0093
diff --git a/src/client.rs b/src/client.rs
index b7163dafc..9e8202483 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -68,6 +68,7 @@ use hbb_common::{
         time::{interval, Duration, Instant},
     },
     webrtc::WebRTCStream,
+    websocket::{check_ws, is_ws_endpoint},
     AddrMangle, ResultType, Stream,
 };
 use base::{
@@ -1848,8 +1849,11 @@ impl Client {
         conn_type: ConnType,
         ipv4: bool,
     ) -> ResultType<Stream> {
+        // The proxy's address family does not constrain the relay target.
+        let relay_server = check_port(relay_server, RELAY_PORT);
+        let use_ws_proxy = Config::is_proxy() && is_ws_endpoint(&check_ws(&relay_server));
         let mut conn = connect_tcp(
-            ipv4_to_ipv6(check_port(relay_server, RELAY_PORT), ipv4),
+            ipv4_to_ipv6(relay_server, ipv4 || use_ws_proxy),
             CONNECT_TIMEOUT,
         )
         .await
diff --git a/src/server.rs b/src/server.rs
index 88341631b..472ab1a8e 100644
--- a/src/server.rs
+++ b/src/server.rs
@@ -21,7 +21,9 @@ use hbb_common::{
     rendezvous_proto::*,
     socket_client,
     sodiumoxide::crypto::{box_, sign},
-    timeout, tokio, ResultType, Stream,
+    timeout, tokio,
+    websocket::{check_ws, is_ws_endpoint},
+    ResultType, Stream,
 };
 use base::message_proto::*;
 use scrap::camera;
@@ -402,8 +404,11 @@ async fn create_relay_connection_(
     ipv4: bool,
     meta: ConnectionMeta,
 ) -> ResultType<()> {
+    // The proxy's address family does not constrain the relay target.
+    let relay_server = crate::check_port(relay_server, RELAY_PORT);
+    let use_ws_proxy = Config::is_proxy() && is_ws_endpoint(&check_ws(&relay_server));
     let mut stream = socket_client::connect_tcp(
-        socket_client::ipv4_to_ipv6(crate::check_port(relay_server, RELAY_PORT), ipv4),
+        socket_client::ipv4_to_ipv6(relay_server, ipv4 || use_ws_proxy),
         CONNECT_TIMEOUT,
     )
     .await?;