Microsoft has announced that’ it’s published the final build of Windows 10 21H1, also known as the Windows 10 May 2021 Update. So what can you expect when it hits your PC? Well, one feature. Okay, maybe two.

No one quite expected Microsoft to release a major Windows 10 feature update in the spring of 2021, given the the work Microsoft has been putting into the forthcoming Windows 10X. Still, few could predict just two consumer-facing features, with only one of them something that a typical user might do. The rest is bug fixes.

In a February blog post, John Cable, Microsoft’s vice president of program management, listed the new features inside Windows 10 21H1. In April, Microsoft senior program manager Brandon LeBlanc confirmed that the feature list has remained unchanged: 

Windows Hello multicamera support to allow users to choose an external Windows Hello camera priority when using high end displays with integrated Windows Hello cameras. 
Windows Defender Application Guard (WDAG) performance improvements including optimizing document opening scenario times.
In other words, if you own a laptop with an integrated camera, but opted to buy a higher-end Windows Hello webcam that you can use instead, Windows will now prioritize the better camera. And if you surf the darker regions of the web, or are just a bit paranoid, Windows 10’s Windows Defender Application Guard allows you to use what’s essentially the Edge browser within a Hyper-V sandbox, so malware can’t break out of the sandbox and infect your computer.

The update improves how WDAG performs. The fixes include solving a potential one-minute delay when opening an Office document within WDAG, and a second that caused a WDAG container to use almost 1 GB of memory when the container is idle.We’d like to believe that you use WDAG as you surf the web—but you probably don’t.

A third upgrade, “Windows Management Instrumentation (WMI) Group Policy Service (GPSVC) updating performance improvement to support remote work scenarios,” probably benefits enterprise administrators more than anyone. 

A fourth fix includes copy performance when copying files over 400MB in size.

 If you’re interested in reviewing exactly what 21H1 will fix, they’re listed as part of a separate build’s release notes, version 19042.844. 

https://www.pcworld.com/article/3608329/microsofts-next-windows-10-21h1-has-essentially-one-new-feature-here-it-is.html