It only sort of does, unfortunately. The extension needed to make this work fully is only on Chrome, unless there's a Firefox version that's recently been released that I'm unaware of.

That said, without using the extension, you can still plug in the CSS for some of the legwork and work with Plurk's default appearance settings to get the rest of it as close as possible. If you'd like some help with this, I'd be more than happy to look at the settings and find something that could work for you. But it definitely won't look exactly like the example, I'm afraid.