Windows 10 build 21277 rolls out to Insiders in the Dev Channel

[Windows Central]

64-bit app emulation, new emoji, improved animation, and more.
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.

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