A leaked screenshots of the 'Spartan' browser has been posted online by Neowin.

"Spartan runs in a borderless window that allows your content to stretch from edge to edge. This means that there is nothing at the bottom of the window to see and all of the new UI elements are at the top of the browser," Neowin, the publication behind the leaks stated.

The new browser, codenamed at this point as Spartan, will be unveiled on January 21, in the company's hometown of Redmond, Washington, when Microsoft shows off Windows 10 for the first time.
    
Spartan may make its formal debut there, but the general release of Windows 10 is not expected until the fall, so it may come at a later date.
    
Thomas Nigro, a Microsoft Student Partner lead and developer of the modern version of VLC a media playing app, claimed on Twitter earlier this month that he heard Microsoft was building a brand-new browser.
    
"Ok so Microsoft is about to launch a new browser that's not Internet Explorer and will be the default browser in Windows 10. Wow," he had tweeted.
    
Spartan will look and feel more like Chrome and Firefox, however, it will support extensions, reports said. The "lightweight" browser will be available on both desktop and mobile devices in Windows 10, they said.
    
Internet Explorer has a poor reputation among developers and users, much of which is rooted in Microsoft's traditional preference for proprietary tools over open standards.
    
Although that stance has changed considerably since the early days of IE, the stigma about it is so great that Microsoft recently made an ad explaining that the browser's poor reputation is not deserved.