Ladies and gentlemen, this is what Windows 10 default browser "Spartan" looks like. Yep, it looks ugly, that's because it's from an older beta version of the Spartan browser.
Update: This screenshot has been confirmed as a FAKE!
The browser appears to have a minimalistic design, featuring clear, straightforward and clutter-free UI elements, supports extensions, as what we already knew about it. But the image source BGR also says that Spartan will let you speak entire voice commands such as "add to favorites", "make it my home homepage," or "go to Facebook.com."