ADDITIONAL SYSTEM INFORMATION :
Checked on Windows, Linux

A DESCRIPTION OF THE PROBLEM :
When a table has many rows, there is a noticeable performance degradation when rendering bottom of the table.

Works fine when showing upper part of the table.
Problem occurs on version 19-ea+9 and up.

REGRESSION : Last worked in version 18.0.2.1

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
TableView with many rows:
 - scroll to the bottom
 - try to resize window, or select one row and then press (and hold) up/down arrow to select other rows
You should see lagging during window resize, selecting rows or table scrolling


---------- BEGIN SOURCE ----------
public class App extends Application {

    @Override
    public void start(Stage stage) throws Exception {
     List<String> rows = IntStream.rangeClosed(1, 1000_000).boxed()
     .map(i -> "row-" + i)
     .collect(Collectors.toList());
    
        TableView<String> tableView = new TableView<>();
        TableColumn<String, String> tc = new TableColumn<>("column-1");
        tc.setCellValueFactory(p -> new ReadOnlyStringWrapper(p.getValue()));
        tc.setPrefWidth(200);
tableView.getColumns().add(tc);
tableView.setItems(FXCollections.observableArrayList(rows));

        var scene = new Scene(new StackPane(tableView), 250, 200);
        stage.setScene(scene);
        stage.show();
        
        tableView.scrollTo(rows.size());
    }

    public static void main(String[] args) {
        launch();
    }

}
---------- END SOURCE ----------

FREQUENCY : always