It's not clear at all from your comment that opening the URL would immediately engage my computer in an attempted attack. I really would have liked an explicit

It's not clear at all from your comment that opening the URL would immediately engage my computer in an attempted attack. I really would have liked an explicit warning. The JS on the page actually froze my browser; I had to force-quit it, turn off my wifi, and then open it again to be able to close the tab.