Test SVGElementInstance.childNodes.
The test has an optional subtest that indicates whether SVGElementInstance.firstChild and SVGElementInstance.childNodes.item(0) are strictly equal. The status of this subtest is displayed by a circle in the middle of the testframe, it will be yellow if the objects are not strictly equal, and green if they are.
Run the test. No interaction required.
The test is passed if there is a green rect visible, and there is a yellow or dark green circle in the middle. If there's any red visible the test has failed.