Run this code to reproduce the issue:

    @Override
    public void start(Stage primaryStage) {
        BorderPane root = new BorderPane();
        
        Pane pane = new Pane();
        
        pane.getChildren().add(new Text("Text"));
        
        root.setCenter(pane);
        
        Scene scene = new Scene(root, 500, 500);
        primaryStage.setTitle(VersionInfo.getRuntimeVersion());
        primaryStage.setScene(scene);
        primaryStage.show();
    }

The code creates an empty scene. If the line "Pane pane = new Pane();" is changed to "Pane pane = new StackPane();" the text will be shown on the screen.