为什么jQuery'nth-child'选择器在GreaseMonkey（0.8）中不起作用？

I believe jQuery's :nth-child selector doesn't work inside GreaseMonkey 0.8. (At the bottom is a quick GM script to test this.) Why is this? Is this a known limitation from working inside GreaseMonkey? Can anyone recommend a way around this?I believe jQuery's :nth-child selector doesn't