x64 emulation rolls out for Windows 10 on ARM in latest Dev Channel release

Microsoft is back with TWO Windows 10 Insider Preview builds today, build 20274 and 21277. Build 21277 is back on the usual rs_prerelease track, and features a bunch of new improvements and changes including emoji support! On ARM PCs, this build also includes 64-bit app emulation.

Because Microsoft is rolling out two builds today, build 21277 is an "optional download" meaning it's something you'll have to manually click on to download if you want it. Insiders in the Dev Channel will otherwise get build 20277, which has only minor fixes in it.

The full changelog for build 21277:

• Windows Insiders with ARM PCs who install this build can try out x64 emulation by installing x64 apps from the Microsoft Store or from any other location of their choosing. For more details on this experience, please head on over and read this blog post from Hari Pulapaka!
• Starting with this build, Insiders will get their first look at the emoji we've designed to support Emoji 12.1 and 13.0! This update brings over 200 new glyphs to Windows – including bubble tea, a smiling face with tear, a ninja, a magic wand, and more:
• We've updated the animation when opening or closing a window to make the transition smoother. Do you notice a difference? Let us know!
• Based on Insider feedback, you can now use the built-in screen snipping experience in Windows (WIN + SHIFT + S) to create a snip of your screen and paste it directly into a folder of your choice in File Explorer to save the screenshot there. Try it out! (This was released to Windows Insiders in the Beta Channel as part of the recent Windows Feature Experience Pack update.)
• Using the touch keyboard in a portrait posture on a 2-in-1 touch device now supports split keyboard mode. (This was released to Windows Insiders in the Beta Channel as part of the recent Windows Feature Experience Pack update.)
• It's now possible to uninstall the Snipping Tool. If you choose to uninstall it, it can be reinstalled via the Optional Features page in Settings.
• We've made some adjustments to improve the scaling logic of the graphs in Task Manager's Performance tab.
• We've updated Registry Editor so that the Find window, renaming a key, and other places all now support CTRL + Backspace to delete words at a time.
• When using the Delete key or Dismiss button in Action Center to clear groups of notifications, Narrator will now announce that the notification group has been cleared instead of just moving focus to the next notification group.
• Based on feedback we're adjusting a few strings in Offline Maps Settings to improve clarity.
• To help you find what you're looking for faster, we've updated our folder logic in Start menu's all apps list so that if a folder only contains a single item we will now display that item in place of the folder.

As always, you can check out the full changelog at the Windows Blog, including a list of known issues.