update

Pilz/Data/Json/JsonFileContainer.cs

@@ -13,6 +13,8 @@ public class JsonFileContainer(string filePath) : JsonDataContainer
                 using var sw = new StreamReader(filePath);
                 GetSerializer().Populate(sw, this);
             }
+            else
+                sets.Clear();
         }
     }
 

Pilz/Data/Json/JsonStreamContainer.cs

@@ -7,9 +7,14 @@ public class JsonStreamContainer(Stream stream) : JsonDataContainer
     {
         lock (_lock_StreamAction)
         {
-            using var sw = new StreamReader(stream);
+            if (stream.Length != 0)
-            stream.Position = 0;
+            {
-            GetSerializer().Populate(sw, this);
+                using var sw = new StreamReader(stream);
+                stream.Position = 0;
+                GetSerializer().Populate(sw, this);
+            }
+            else
+                sets.Clear();
         }
     }