diff --git a/addons/bus/tests/common.py b/addons/bus/tests/common.py
index 10e7fcf40ea..1fe03983909 100644
--- a/addons/bus/tests/common.py
+++ b/addons/bus/tests/common.py
@@ -77,6 +77,8 @@ class WebsocketCase(HttpCase):
         ws = websocket.create_connection(
             type(self)._WEBSOCKET_URL, *args, **kwargs
         )
+        ws.ping()
+        ws.recv_data_frame(control_frame=True) # pong
         self._websockets.add(ws)
         return ws
 
diff --git a/addons/bus/tests/test_websocket_caryall.py b/addons/bus/tests/test_websocket_caryall.py
index 60201cf10be..f9d5f15618e 100644
--- a/addons/bus/tests/test_websocket_caryall.py
+++ b/addons/bus/tests/test_websocket_caryall.py
@@ -241,8 +241,10 @@ class TestWebsocketCaryall(WebsocketCase):
         new_test_user(self.env, login='test_user', password='Password!1')
         user_session = self.authenticate('test_user', 'Password!1')
         serve_forever_called_event = Event()
+        original_serve_forever = WebsocketConnectionHandler._serve_forever
 
         def serve_forever(websocket, *args):
+            original_serve_forever(websocket, *args)
             self.assertNotEqual(websocket._session.sid, user_session.sid)
             self.assertNotEqual(websocket._session.uid, user_session.uid)
             serve_forever_called_event.set()