This is a really bogus new item.

You can see from the page's HTML that all the traffic light does is tell you if it is currently the sabbath, which it does by looking at the date and time with Javascript. There is no magic here to change the status dynamically based on anything except the current time and date.

The HTML is a long way from being standards compliant, so I'm not surprised it renders differently in different browsers. Mac IE renders it fine.