handle newly added columns

stand.py

@@ -24,6 +24,12 @@ changed = restapi.changed
 df = restapi.data
 
 
+columns = st.session_state.get("columns", set())
+new_columns = set(df.columns)
+cols_changed = (columns != new_columns)
+st.session_state.columns = new_columns
+
+
 
 print(">>> start of streamlit run")
 
@@ -73,7 +79,7 @@ response = AgGrid(
     fit_columns_on_grid_load=True,
 
     reload_data=changed,
-    key="stand"
+    key=None if cols_changed else "stand" # None triggers a hard reload like F5, which is needed if new columns were added
 )