TextArea initial appearance is corrupted

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextArea;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class TextAreaSample extends Application {

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

    @Override
    public void start(Stage stage) throws Exception {
        Pane pane = new Pane();
        pane.setPrefSize(600, 600);
        pane.getChildren().add(new Button("Button"));

        HBox root = new HBox(3);
        root.getChildren().add(pane);
        root.getChildren().add(new VBox(new Button("Button"), new TextArea()));

        stage.setScene(new Scene(root, 800, 600));
        stage.show();
    }
}