diff --git a/CHANGES.rst b/CHANGES.rst
index a42ec92f9a53149ce26332bff518883f23e15946..2014348334785a9d9b6115aa0e5f7bb6796f8c9d 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -9,6 +9,12 @@ Changes
 =======
 
 
+Version 2025.1.9 (released 2025-02-13)
+
+- Allow secondary email address to be removed again
+- Add "id" to the fake entity created by `SystemEntityProxy._resolve()`
+
+
 Version 2025.1.8 (released 2025-02-13)
 
 - Explicitly set calculated value for `THEME_SITEURL` in the config
diff --git a/invenio_config_tuw/__init__.py b/invenio_config_tuw/__init__.py
index a902ac3ac244dab1aec9fd1eca6a89960d726f71..f3aeeaaec3d7b39a093d7172a80944c07258c271 100644
--- a/invenio_config_tuw/__init__.py
+++ b/invenio_config_tuw/__init__.py
@@ -9,6 +9,6 @@
 
 from .ext import InvenioConfigTUW
 
-__version__ = "2025.1.8"
+__version__ = "2025.1.9"
 
 __all__ = ("__version__", "InvenioConfigTUW")
diff --git a/invenio_config_tuw/notifications/entity_resolvers.py b/invenio_config_tuw/notifications/entity_resolvers.py
index e6fc90ad6c2157bdbaa8303f524249077ed6a78d..5d2c0430887655dbed8063a28550881dd638d45b 100644
--- a/invenio_config_tuw/notifications/entity_resolvers.py
+++ b/invenio_config_tuw/notifications/entity_resolvers.py
@@ -27,7 +27,11 @@ class SystemEntityProxy(EntityProxy):
         Since this will mostly be used in Jinja templates, it being a dictionary
         and not an actual object is fine.
         """
-        return {"username": "system", "user_profile": {"full_name": "System"}}
+        return {
+            "id": "system",
+            "username": "system",
+            "user_profile": {"full_name": "System"},
+        }
 
     def pick_resolved_fields(self, identity, resolved_dict):
         """Select which fields to return when resolving the reference."""
diff --git a/invenio_config_tuw/users/schemas.py b/invenio_config_tuw/users/schemas.py
index 3134866f4e9731a34ff3c885b69d6663451a8e08..41e10402a760b19e3bc0bf425ecb2d263e243738 100644
--- a/invenio_config_tuw/users/schemas.py
+++ b/invenio_config_tuw/users/schemas.py
@@ -15,7 +15,7 @@ from invenio_users_resources.services.schemas import (
     NotificationPreferences,
     UserProfileSchema,
 )
-from marshmallow import fields
+from marshmallow import fields, pre_load
 
 
 # profile
@@ -33,6 +33,14 @@ class TUWNotificationPreferencesSchema(NotificationPreferences):
 
     secondary_email = fields.Email()
 
+    @pre_load
+    def remove_empty_secondary_mail(self, data, **kwargs):
+        """Turn empty string for secondary emails into `None`."""
+        if not data.get("secondary_email"):
+            data.pop("secondary_email", None)
+
+        return data
+
 
 class TUWUserPreferencesSchema(UserPreferencesSchema):
     """User preferences schema with TU Wien extensions."""