FXML: ParseTraceElement.toString() throws error when xml is loaded from InputStream

___________________________ code src fragment _________________
       ...
           URL resourceURL1 = getClass().getResource("some correct path here");
       ...
            InputStream is = null;
            System.out.println("loading RES 1 / " + resourceURL1);
            try {
                is = resourceURL1.openStream();
                fxmlLoader.load(is);
        ....
________________________________________________________________


NPE:


java.lang.NullPointerException
at javafx.fxml.ParseTraceElement.toString(ParseTraceElement.java:34)
at java.lang.String.valueOf(String.java:2902)
at java.lang.StringBuilder.append(StringBuilder.java:128)
at test.fxmltests.app.staticPropertyLoadApp$loadExceptionsSlot.impl_drawNode(staticPropertyLoadApp.java:950)
at test.fxmltests.app.staticPropertyLoadApp$TestNodeWithIOExceptionProcessing.drawNode(staticPropertyLoadApp.java:133)
at test.javaclient.shared.TestNode.draw(TestNode.java:115)
at test.javaclient.shared.PageWithSlots.drawTo(PageWithSlots.java:72)
at test.javaclient.shared.CombinedTestChooserPresenter.showTestNode(CombinedTestChooserPresenter.java:126)
at test.javaclient.shared.AbstractApp2$2.run(AbstractApp2.java:192)
at com.sun.javafx.application.PlatformImpl$3.run(PlatformImpl.java:141)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access$100(WinApplication.java:29)
at com.sun.glass.ui.win.WinApplication$2$1.run(WinApplication.java:62)
at java.lang.Thread.run(Thread.java:722)