to reproduce run following code



import javafx.application.Application;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class ButtonBackgroundSize extends Application {

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

    private Parent getContent() {
        VBox list = new VBox(10);
        
        Button but = new Button("Button long long line\n the\n\n\n\n\n\n first line");
        but.setStyle("-fx-background-image: "
                    + "url(\"file:red-rectangle.png\");"+"-fx-background-size: 100% 100%;-fx-border-color: red;");
       
        list.getChildren().add(but);
        return list;
    }

    public void start(Stage stage) {
        stage.setX(100);
        stage.setY(100);
        stage.setWidth(200);
        stage.setHeight(200);
        Scene scene = new Scene(getContent());
        stage.setScene(scene);
        stage.setVisible(true);
    }
}
///////////////////////////////////////




import javafx.application.Application;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class ButtonBackgroundSize extends Application {

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

    private Parent getContent() {
        VBox list = new VBox(10);
        Button but = new Button("Button long long line\n the\n\n\n\n\n\n first line");
        but.setStyle("-fx-background-image: "
                + "url(\"file:red-rectangle.png\");" + "-fx-background-size: 50%;"
                + "-fx-background-repeat: no-repeat;");
        list.getChildren().add(but);
        return list;
    }

    public void start(Stage stage) {
        stage.setX(100);
        stage.setY(100);
        stage.setWidth(400);
        stage.setHeight(400);
        Scene scene = new Scene(getContent());
        stage.setScene(scene);
        stage.setVisible(true);
    }
}
/////////////////////////////////////////////////


import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class ButtonBackgroundSizeDirtyRegions extends Application {
    Button but;
     VBox list;
    public static void main(String[] args) {
        launch(args);
    }

     private Parent getContent() {
        list = new VBox(10);
        but = new Button("Button long long line\n the\n\n\n\n\n\n first line");
        but.setStyle("-fx-background-image: "
                + "url(\"file:red-rectangle.png\");" + "-fx-background-size: 300%;"
                + "-fx-background-repeat: no-repeat;-fx-border-color:green;");
        list.getChildren().add(but);
        return list;
    }

    public void start(Stage stage) {
        stage.setX(100);
        stage.setY(100);
        stage.setWidth(400);
        stage.setHeight(400);
        Scene scene = new Scene(getContent());
        stage.setScene(scene);
        stage.show();
        new Thread(new Runnable(){

            @Override
            public void run() {
                try {
                    Thread.sleep(2000);
                } catch (InterruptedException ex) {
                    Logger.getLogger(ButtonBackgroundSize.class.getName()).log(Level.SEVERE, null, ex);
                }
                Platform.runLater(new Runnable(){

                    @Override
                    public void run() {
                        list.getChildren().remove(but);
                    }
                });
            }
        }).start();
    }
}