According to a few sources from within Microsoft, it appears that the company is working on a new web browser — codenamed Spartan — that will debut with Windows 10. Spartan will reportedly look like a mix of Firefox and Chrome, with tabs above the address bar — and, perhaps most excitingly, Spartan will apparently support real browser extensions. (Extensions/add-ons in current versions of Internet Explorer are a bit of a joke.)

Back in September, just before the first Windows 10 Technical Preview, there were some rumblings that the future version of Internet Explorer (i.e. IE12) might support extensions, and that it would have a reworked interface. Now, ZDNet and Neowin are reporting — from fairly reliable sources — that there may actually be two different browsers that ship with Windows 10: Internet Explorer 12, and this new Spartan browser. Neither of these browsers (if they exist) have yet made an appearance in the public Technical Preview, but presumably they would have to emerge quite soon if they want to debut with the final build of Windows 10.

According to the various reports, Spartan (which is just a codename right now) is a new web browser, but it uses the same Trident rendering engine and Chakra JavaScript engine as Internet Explorer. The rest of the browser would be different, though: It would have a different UI — something like Firefox or Chrome, with the tabs on top — and allow for extensions. Extensions (add-ons in Firefox parlance) could be very interesting, though we should wait and see what Microsoft’s implementation is before we get too excited. Microsoft would have to create a completely new front-end to allow for powerful, Firefox-like extensions — which would take a lot of work.

Read: The Browser Cold War

According to Neowin, Spartan “looks a lot like Chrome but with Microsoft’s flat lipstick applied.” To be honest, Internet Explorer 11 is already quite flat, so presumably the big change is dropping the address bar below the tabs. (Amusingly enough, Microsoft originally moved the address bar in-line with the tabs to reduce the amount of vertical pixels wasted by the browser UI — so it would be a bit of a regression to have tabs on their own row, starting in the top left corner of the window.)

Personally, I’m not entirely sure how Microsoft would go about accomplishing a lightweight (read: spartan) version of Internet Explorer. IE11 is already fast and lightweight. It has a few user experience and interface oddities that need to be cleaned up, but that could be done without a whole new browser. Another possibility is that Microsoft is actually working on more of a general rebranding — as in, a hip new interface and name that puts some distance it and ye olde Internet Explorer. Internet Explorer hasn’t really been “IE” since IE9, when Microsoft started to embrace HTML5 and the open web — but I’m sure many people still avoid IE because of the stigma attached to its name, thanks to the scourge upon humanity that is IE6.

As for what Microsoft’s new web browser might be called, we could find out at the next Windows 10 unveil event on January 21. My money is on something confusing, like “Modern Browser” or maybe “Explorer One.”

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