Press This doesn’t work?

I dragged that Press This bookmarklet to my bookmarks and tried it on a page. All I got was a public side page (not an editing post interface) that says “Error 404 – Not Found Sorry, the page that you are looking for does not exist.” Tried this on several different webpages and on a different computer but it always does the exact same thing. WTF? It’s not sending me to an editing page, it always sends me to a public side page which doesn’t exist. WTF again.