Microsoft enabled full support for asm.js for Windows Insider builds 10532 and up yesterday. Since it is generally assumed that the long-awaited TH2 update for stable versions of Windows is 10586, it will be available on those systems this month as well since Microsoft plans to roll out the TH2 update to all systems this month.
Microsoft enables full support for asm.js on Windows 10
http://www.ghacks.net/2015/11/11/microsoft-enables-full-support-for-asm-js-on-windows-10/
