Scenario: avoid marking loaded scenario data as modified, that created unwanted copies in database

src/Model/Study.py

@@ -572,16 +572,20 @@ class Study(SQLModel):
             "scenario": scenario
         }
 
-        # Load river data
-        river = River._db_load(
-            sql_exec, data=data
-        )
-        data["study"] = self
-        river._db_load_results(sql_exec, data=data)
+        self.status.start_loading()
+        try:
+            # Load river data
+            river = River._db_load(
+                sql_exec, data=data
+            )
+            data["study"] = self
+            river._db_load_results(sql_exec, data=data)
+        finally:
+            self.status.stop_loading()
+            self.status.scenario = old_scenario
 
         # FIXME: Disable scenario cache to save memory usage
         # self._river_scenario_cache[scenario] = river
-        self.status.scenario = old_scenario
 
         return river