diff --git a/addons/payment_paypal/controllers/main.py b/addons/payment_paypal/controllers/main.py
index 4d3d623fbbc..c170b1d4068 100644
--- a/addons/payment_paypal/controllers/main.py
+++ b/addons/payment_paypal/controllers/main.py
@@ -16,12 +16,23 @@ class PaypalController(http.Controller):
     _return_url = '/payment/paypal/dpn/'
     _notify_url = '/payment/paypal/ipn/'
 
-    @http.route(_return_url, type='http', auth='public', methods=['GET', 'POST'], csrf=False)
+    @http.route(
+        _return_url, type='http', auth='public', methods=['GET', 'POST'], csrf=False,
+        save_session=False
+    )
     def paypal_dpn(self, **data):
         """ Route used by the PDT notification.
 
         The "PDT notification" is actually POST data sent along the user redirection.
         The route also allows the GET method in case the user clicks on "go back to merchant site".
+
+        The route is flagged with `save_session=False` to prevent Odoo from assigning a new session
+        to the user if they are redirected to this route with a POST request. Indeed, as the session
+        cookie is created without a `SameSite` attribute, some browsers that don't implement the
+        recommended default `SameSite=Lax` behavior will not include the cookie in the redirection
+        request from the payment provider to Odoo. As the redirection to the '/payment/status' page
+        will satisfy any specification of the `SameSite` attribute, the session of the user will be
+        retrieved and with it the transaction which will be immediately post-processed.
         """
         _logger.info("handling redirection from Ogone with data:\n%s", pprint.pformat(data))
         try: