unfortunately I can't reproduce it anymore

I run this snippet and close the window:
public void start(Stage stage) throws Exception {
        
        Text text = new Text("hi");
        text.setStyle("-fx-fill: blue;-fx-stroke: red;");
VBox box = new VBox();
box.getChildren().add(text);
Scene scene = new Scene(box, 300, 300);
// scene.getStylesheets()
stage.setTitle("My JavaFX Application");
stage.setScene(scene);
stage.show();
}

Message in the console:

java.lang.NullPointerException
at com.sun.javafx.tk.quantum.ViewPainter.validateStageGraphics(ViewPainter.java:75)
at com.sun.javafx.tk.quantum.PresentingPainter.run(PresentingPainter.java:30)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRunAndReset(FutureTask.java:351)
at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:178)
at com.sun.prism.render.RenderJob.run(RenderJob.java:37)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at com.sun.javafx.tk.quantum.QuantumRenderer$PipelineRunnable.run(QuantumRenderer.java:96)
at java.lang.Thread.run(Thread.java:722)
2012-06-01 15:31:22.522 java[19085:5703] *** -[NSRecursiveLock unlock]: lock (<NSRecursiveLock: 0x7f817a5a3eb0> '(null)') unlocked when not locked
2012-06-01 15:31:22.526 java[19085:5703] *** Break on _NSLockError() to debug.
2012-06-01 15:31:22.526 java[19085:5703] *** Assertion failure in -[NSWindowGraphicsContext reenableFlush], /SourceCache/AppKit/AppKit-1138.47/GraphicsContext.subproj/NSWindowGraphicsContext.m:170
2012-06-01 15:31:22.549 java[19085:5703] unlockFocus caught exception: Invalid parameter not satisfying: _flushDisableCount > 0
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