Sample and bug description is provided by doc writers. To reproduce:
- scroll down the content of ListView using mouse and scroll bar knob
- increase ListView height dragging window edge by mouse
A ghost list item appears.
setGraphic(null) in updateItem() solves the problem.

package listviewsample;

import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.layout.Priority;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.scene.text.Font;
import javafx.stage.Stage;
import javafx.util.Callback;

public class Main extends Application {

    ListView<String> list = new ListView<String>();
    ObservableList<String> data = FXCollections.observableArrayList(
            "chocolate", "salmon", "gold", "coral", "darkorchid",
            "darkgoldenrod", "lightsalmon", "black", "rosybrown", "blue",
            "blueviolet", "brown");
    final Label label = new Label();

    @Override
    public void start(Stage stage) {
        VBox box = new VBox();
        Scene scene = new Scene(box, 200, 200);
        stage.setScene(scene);
        stage.setTitle("ListViewSample");
        box.getChildren().addAll(list, label);
        VBox.setVgrow(list, Priority.ALWAYS);

        label.setLayoutX(10);
        label.setLayoutY(115);
        label.setFont(Font.font("Verdana", 20));

        list.setItems(data);

        list.setCellFactory(new Callback<ListView<String>, ListCell<String>>() {
            @Override public ListCell<String> call(ListView<String> list) {
                return new ColorRectCell();
            }
        });
 
        list.getSelectionModel().selectedItemProperty().addListener(
                new ChangeListener<String>() {
                    public void changed(ObservableValue<? extends String> ov,
                        String old_val, String new_val) {
                            label.setText(new_val);
                            label.setTextFill(Color.web(new_val));
                    }
                });
        stage.show();
    }
    
    static class ColorRectCell extends ListCell<String> {
        @Override
        public void updateItem(String item, boolean empty) {
            super.updateItem(item, empty);
            Rectangle rect = new Rectangle(100, 20);
            if (item != null) {
                rect.setFill(Color.web(item));
                setGraphic(rect);
            }/* else {
                setGraphic(null);
            }*/
        }
    }
    
    public static void main(String[] args) {
        launch(args);
    }
}