GaussianBlur always renders at 1:1 scale and may be unnecessarily blurry in a scaled scene

In the following code, the second button is blurred (and should not be?):

package test;

import javafx.application.*;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.scene.effect.*;
import javafx.stage.*;

public class BugBlur extends Application {

public static void main(String[] args) {
Launcher.launch(BugBlur.class, args);
}

public void start(final Stage stage) {
Group group = new Group ();

Button button = new Button ("TEST");
button.setLayoutX(100);
button.setLayoutY(100);
button.setScaleX(2);
button.setScaleY(2);
group.getChildren().add(button);

Button button2 = new Button ("TEST");
button2.setLayoutX(100);
button2.setLayoutY(150);
button2.setScaleX(2);
button2.setScaleY(2);
group.getChildren().add(button2);
GaussianBlur blur = new GaussianBlur();
blur.setRadius(0);
button2.setEffect(blur);

Scene scene = new Scene(group);
stage.setScene(scene);
stage.setVisible(true);
}
}