With Windows Insider builds appearing as often as twice a week this past year, the notion of a “leaked” build seems almost quaint. But a newly leaked build of Windows 10 version 1703 provides an interesting dose of both nostalgia and promise. And in some ways, this build shows off more of what we can expect in the Windows 10 Creators Update than any of the previous builds.

Note: News of this leaked build was first reported by Windows Central.

As you may recall, Microsoft plans to ship two major updates to Windows 10 in 2017. The first, called the Creators Update and previously codenamed “Redstone 2,” is expected in March, and it will upgrade Windows 10 to version 1703. (The current version is 1607, for its July 2016 release date.) The second update is due more vaguely in the second half of 2017 and still goes by its “Redstone 3” codename.

This newly leaked build is, of course, part of the Windows 10 version 1703 pre-release work on which Microsoft is currently working. It is build 14997, a smallish bump from the previous Windows Insider release, which was build 14986. That build arrived on December 7, just ahead of Microsoft’s mid-December work stoppage, and while Microsoft had hoped to ship one more build before the entire campus basically emptied, none achieved the desired level of quality.

Build 14997 comes from the “rsonecorebase” development branch, which offers a subset of what we typically see from the Insider builds. (The Insider builds aggregate new features and fixes from across the various development branches.) So rsonecorebase is, as its name suggests, related to the common core of the OS—the kernel, of course, but also common shared code—that works across platforms. And in this case what we’re seeing is what we might have seen had Microsoft gotten an Insider build out the week of December 12. (The build is dated December 18, 2016.)

And now we can see why they were so keen to do so: Build 14997 is chock full of new features, something we’ve only seen once or twice since the Creators Update announcement. This would have been a fine Christmas/Hanukkah/whatever present for Microsoft’s biggest fans if they could have pulled it off.

But we don’t need to wait for January to see the new Insider build. Instead, we just have to wait for the leaked build to download. Which is going to take a while. So in the meantime, I’ll base this first peek on the features Windows Central has dug up so far, but I’ll add my own perspective for a deeper understanding of what’s really happening here.

Here’s what’s new.

Cortana comes to Setup. As you may know from reading the Windows 10 Field Guide, Windows 10 Setup is divided into two major interactive phases, the second of which was once called the Out Of Box Experience, or OOBE. This is the part of Setup where you add the first user to the PC, determine whether to use Express settings, and the like. In build 14997, Setup has been enhanced—well, changed—to include Cortana voice control, so you can speak to the PC instead of clicking buttons and filling out text fields. This is actually a pretty terrible idea, but I think Microsoft is looking ahead to a point where this actually works well and is a normal way to interact with technology. And of course you can make the claim that it’s more accessible, which is never a negative.

Start menu folders. Answering a long-standing customer request, Microsoft has added expandable/collapsible folders to the tiles area of the Start menu, just like we had via Live Folders in Windows phone 8.1.1, which debuted in mid-2014. Why this feature was never included in Windows 10 is unclear, but it looks like it will finally make the cut in the fourth major version of the OS.

Microsoft Edge improvements. Microsoft’s woeful web browser continues to inch forward slowly. This build includes a new “Set these tabs aside” toggle that lets you, um, set tabs aside so they don’t take up all that space in the tabs row. And there’s a new Tab Preview view that lets you preview all open tabs so you can easily find the right one.

New Share UI. As promised at the Creators Update announcement, Microsoft is revising the Share UI in Windows 10 to include a simple new pop-up based interface that replaces the Share pane that dates back to Windows 8.0. In build 14997, you can see this new UI in any app that uses Share. But the My People feature, which will also use the new Share, is apparently not available.

Cortana changes. Previous to Windows 10 version 1607, you could type WINKEY + C to access Cortana, even if it was hidden on the taskbar. In 1703, WINKEY + C is making a comeback, where you can use this shortcut to toggle Cortana’s listening mode. That means you can easily toggle it off when it gets annoying.

Windows Update improvements. Microsoft had previously promised to make Windows Update less painful, and proving how easy that can be, build 14997 includes a new Pause Updates option in Windows Update that lets you temporarily pause the delivery of new updates for up to 35 days. This should nicely answer complaints about the quality of newly-released updates, since the more pragmatic will be able to hold off until they’re proven safe. (Some updates, like those for Windows Defender, will of course continue to come through on the normal schedule, Microsoft notes.)

Settings improvements. No, Control Panel isn’t going away in this build, and it’s weird that people want this so badly. But Settings has been updated in minor ways in build 14997, with a new Apps top-level choice, pulling that out of System, and subtle improvements throughout Settings. The long-awaited Blue light setting, which works like f.lux, also makes its debut. You may recall that Brad wrote about this addition earlier in 2016.

Windows Defender improvements. In the current Insider builds, there’s a new Windows Defender modern app that’s a sort of front-end to the real (Win32) Defender applications, but it’s very sparse. In this new build, that modern app has been built out and now offers a Security Center-like dashboard for all of the PC’s security features. They should just call it Security Center, frankly. Too obvious?

But wait, there’s more. There are numerous other small changes, of course. None worth highlighting.

I won’t be putting this on a real PC, as that’s what virtual machines are for. So I’ll try to dig up more later today. But if you’re interested in testing this build—you crazy person, you—-look for a file named10.0.14997.1001.rsonecorebase.161218-0833amd64freclient-enterprisevolumeen-us-CENA_X64FREVEN-USDV5. The truth is out there.