Here is the changelog for Windows 10 build 10586.240 (PC) and 10586.242 (Phone)

[WindowsCentral.com]

Microsoft released a surprise cumulative update for Windows 10 for PC and Windows 10 Mobile for those on the Release Preview Ring for the Insider Program. That ring is for some last minute testing before the general production release and is the safest of all the Insider levels.

Through the Feedback Hub Microsoft has posted the changelog. As it turns out, the PC version goes to build 10586.240 while the Mobile version heads to 10586.242. Having said that, the fixed and improved list is the same for both releases. Here is what's new.

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