New features in Windows 10 Insider Preview Build 14901

by evil_pro3 years ago

Today, Microsoft released the first build of Redstone 2 to Windows Insiders in the Fast ring.
The official changelog lacks quite a few things, which I’m trying to cover here. I will also list hidden stuff that’s found.

Microsoft Edge

There are some new features in Edge compared to the last release.

You’re now able to switch between the Stable, Selfhost and Canary composition engines. Judging by the names, it sounds like this is an internal leftover which might get removed in the future. Additionally, they’ve added a new checkbox in the WebRTC category to enable WebRTC 1.0. The biggest change is the addition of Service Workers, which can now be enabled on the about:flags page. The last Edge change that’s been found so far is an option at the very bottom to enable Fetch Based Network Stack.

Edge ServiceWorkers

People Band

This feature made its initial appearance in the very first public build of Windows 10, 9841, that got released to Windows Insiders back in October of 2014.

YouTube user winutiae found a rather complicated way to enable the feature back then.

According to Core, the People Bar got an update in this build. There is no known way of enabling the feature on 14901 at the time I’m writing this. If you’re a developer and want to mess with it, there are PeopleBar.dll and PeopleBarHost.dll in System32 waiting for you.

PeopleBarHost Functions

I’ve been informed that in early Threshold 1 builds, the People Band was just a few window classes inside the Taskbar. Now it’s using the IBandSite.

Windows Holographic First Run

This app appears to be designed for HoloLens devices but it seems like it got accidentally included in this build. There’s nothing interesting in the app either.

I’ll show you a screenshot anyways.


For those wondering, if you press the button it just vanishes. Interestingly, that button checks for network connectivity.


The setup got a small update. In the Product Key screen, there are now two clickable strings in the lower left.

14901 Setup

Isolated User Mode SDK

Core also spotted an Isolated User Mode SDK that’s in the works in this build.

Isolated User Mode Functions

For more details about what the Isolated User Mode is, I highly suggest watching this TechNet video. It’s really informative.

Spatializer APO

SpatializerAPO.dll appears to be very audio related, as APO stands for Audio Processing Objects and a deeper look into the file reveals XAudio references, which is a DirectX Audio Library.
It is likely that this will be used for HoloLens.

Also, SSDM.dll was added which is very closely related to SpatializerAPO.dll.

Windows Defener Offline

The Windows Defender Offline scan is also being improved with this build.
OfflineScannerShell.exe was added which will give you a bit more control about the offline scan.

Offline Scan OS Selection Dialog

As you can see, you will be able to select the OS you wish to scan in the near future. It isn’t enabled in this build as far as I know (and tried), but the resources for it are there.

Offline Scan Loading Dialog


If you find something else in this build that’s new and hasn’t been mentioned here, feel free to contact me on Twitter.
Special thanks to Core for many tips.