diff --git a/services/web/server/src/simcore_service_webserver/statics/_handlers.py b/services/web/server/src/simcore_service_webserver/statics/_handlers.py
index eed82fa588c..ecda8a0a83e 100644
--- a/services/web/server/src/simcore_service_webserver/statics/_handlers.py
+++ b/services/web/server/src/simcore_service_webserver/statics/_handlers.py
@@ -14,15 +14,13 @@
 
 
 async def get_cached_frontend_index(request: web.Request):
-    # NOTE: always deliver a front-end
     product_name = get_product_name(request)
 
     assert (  # nosec
         product_name in FRONTEND_APPS_AVAILABLE
     ), "Every product is mapped with a front-end app with IDENTICAL name"
 
-    # NOTE: CANNOT redirect , i.e.
-    # raise web.HTTPFound(f"/{target_frontend}/index.html")
+    # NOTE: CANNOT redirect , i.e. `web.HTTPFound(f"/{target_frontend}/index.html")`
     # because it losses fragments and therefore it fails in study links.
     #
     # SEE services/web/server/tests/unit/isolated/test_redirections.py
diff --git a/services/web/server/tests/unit/isolated/test_products_middlewares.py b/services/web/server/tests/unit/isolated/test_products_middlewares.py
index e3b91ce67fd..8dbf517492d 100644
--- a/services/web/server/tests/unit/isolated/test_products_middlewares.py
+++ b/services/web/server/tests/unit/isolated/test_products_middlewares.py
@@ -29,16 +29,22 @@ def mock_postgres_product_table():
 
     column_defaults["login_settings"] = LOGIN_SETTINGS_DEFAULT
 
+    _SUBDOMAIN_PREFIX = r"[\w-]+\."
+
     return [
-        dict(name="osparc", host_regex=r"([\.-]{0,1}osparc[\.-])", **column_defaults),
+        dict(
+            name="osparc",
+            host_regex=rf"^({_SUBDOMAIN_PREFIX})*osparc[\.-]",
+            **column_defaults,
+        ),
         dict(
             name="s4l",
-            host_regex=r"(^s4l[\.-])|(^sim4life\.)|(^api.s4l[\.-])|(^api.sim4life\.)",
+            host_regex=rf"^({_SUBDOMAIN_PREFIX})*(s4l|sim4life)[\.-]",
             **column_defaults,
         ),
         dict(
             name="tis",
-            host_regex=r"(^tis[\.-])|(^ti-solutions\.)",
+            host_regex=rf"^({_SUBDOMAIN_PREFIX})*(tis|^ti-solutions)[\.-]",
             vendor={
                 "name": "ACME",
                 "address": "sesame street",
@@ -68,7 +74,6 @@ def mock_app(mock_postgres_product_table: dict[str, Any]) -> web.Application:
     "request_url,x_product_name_header,expected_product",
     [
         ("https://tis-master.domain.io/", "tis", "tis"),
-        ("https://s4l-staging.domain.com/v0/", "s4l", "s4l"),
         ("https://osparc-master.domain.com/v0/projects", None, "osparc"),
         ("https://s4l.domain.com/", "s4l", "s4l"),
         ("https://some-valid-but-undefined-product.io/", None, FRONTEND_APP_DEFAULT),
@@ -77,10 +82,11 @@ def mock_app(mock_postgres_product_table: dict[str, Any]) -> web.Application:
         ("https://ti-solutions.io/", "tis", "tis"),
         ("https://osparc.io/", None, "osparc"),  # e.g. an old front-end
         ("https://staging.osparc.io/", "osparc", "osparc"),
+        ("https://s4l-staging.domain.com/v0/", "s4l", "s4l"),
         # new auth of subdomains. SEE https://github.com/ITISFoundation/osparc-simcore/pull/6484
         (
-            "https://34c878cd-f801-433f-9ddb-7dccba9251af.services.s4l-solutions.com/notebooks/lab",
-            "s4l",
+            "https://34c878cd-f801-433f-9ddb-7dccba9251af.services.s4l-staging.domain.com",
+            None,
             "s4l",
         ),
     ],
@@ -99,6 +105,7 @@ async def test_middleware_product_discovery(
     url = URL(request_url)
     headers = {
         "Host": url.host,
+        "X-Forwarded-Host": url.host,
     }
     if x_product_name_header:
         headers.update({X_PRODUCT_NAME_HEADER: x_product_name_header})