Microsoft: This new Windows 10 preview is just to test how quickly we can issue builds

Microsoft releases another Windows 10 preview but only to test its ability to flight new previews in rapid succession.

Securing Windows 10 PCs: What to watch out for

Microsoft has released a new Windows 10 preview, build 20279 for Windows Insiders in the Dev Channel – but the point of release is to allow Microsoft to test its update capabilities rather than offer new features or fixes.

"We wanted to test our ability to quickly follow up a flight with another flight," Microsoft Windows Insider program manager Brandon LeBlanc noted in a blogpost

The latest preview today is from the Iron (Fe) branch and contains very few changes to preview build 20277 that it flighted last week to users in the Dev Channel. At the same time last week, it released RS_Prerelease build 21277, which is expected to be designated as the 'Cobalt' branch and could arrive in the second half of 2021. 

SEE: Cheat sheet: Windows 10 PowerToys (free PDF) (TechRepublic)    

LeBlanc also offered an update on which of the branches users in the Dev Channel should be receiving. 

Those who moved to Build 21277 (RS_PRERELEASE) last week will not be offered build 20279 because they're already on a newer build. 

"We are working on getting a new build out to those Insiders soon. We expect to move all Insiders in the Dev Channel back to receiving builds from RS_PRERELEASE sometime after the holidays," he explained.  

The 21277 build included x64 app emulation for Arm, which broadens Windows on Arm support from only 32-bit Intel (x86) apps. 

However, releases in the Dev Branch are not necessarily tied to a specific Windows 10 feature update, so it could appear in 21H1, which is expected to be a small update, or 21H2, which will reportedly be a much bigger update with significant changes to the Windows 10 UI. 

There are a few known issues in the just-released 20279 build, including reports of the update process stalling for extended periods of time when attempting to install a new build. 

SEE: Windows 10's open-source PowerToys: Video meeting mute tool hit by pandemic, says Microsoft

LeBlanc notes that live previews for pinned sites aren't enabled for all Insiders yet, so they may just see a gray window. Microsoft is working on improving this experience. It's also working on a new taskbar experience for existing pinned sites. 

Some users may be seeing that no drives appear when trying to manage disk volumes using Microsoft's modern take on its Disk Management console via the Settings app. This is available in Settings > System > Storage > Manage Disks and Volumes. LeBlanc suggests users can try the classic Disk Management tool instead.