Die falsche Subdomain-Zuordnung wurde behoben.

Website/main.py

@@ -1672,14 +1672,16 @@ def _get_instance_for_user(username, display_name=None, user_id=None):
     user_id = user_id or session.get("user_id")
     client, col = _get_collection("instances")
     try:
-        query = {
-            "$or": [
-                {"owner_username": username},
-                {"username": username},
-                {"owner_id": user_id}
-            ]
-        }
-        return col.find_one(query)
+        ownership_filters = [
+            {"owner_username": username},
+            {"username": username},
+        ]
+        # A missing session user_id must not become {"owner_id": None}: in
+        # MongoDB that also matches legacy documents without an owner_id.
+        if user_id:
+            ownership_filters.append({"owner_id": user_id})
+
+        return col.find_one({"$or": ownership_filters})
     finally:
         client.close()
 
@@ -3828,10 +3830,17 @@ def my_instance_management():
         # Wenn noch keine Instanz da ist, prüfen wir ob eine gerade erstellt wird
         req_client, req_col = _get_collection("instance_requests")
         try:
-            pending_request = req_col.find_one({
-                "user_id": user_id,
-                "provision_status": {"$in": ["pending", "in_progress"]}
-            })
+            pending_query = {
+                "provision_status": {"$in": ["pending", "in_progress"]},
+            }
+            if user_id:
+                pending_query["$or"] = [
+                    {"user_id": user_id},
+                    {"username": username},
+                ]
+            else:
+                pending_query["username"] = username
+            pending_request = req_col.find_one(pending_query)
         finally:
             req_client.close()