Microsoft has released a new Windows 10 Insider Preview Build 17672 (RS5) to Windows Insiders in the Fast ring in addition to those who opted in to Skip Ahead. The update includes the following new features:
Windows Security Improvements
The Windows Security Center (WSC) service now requires antivirus products to run as a protected process to register. Products that have not yet implemented this will not appear in the Windows Security UI, and Windows Defender Antivirus will remain enabled side-by-side with these products.
For testing purposes, you can disable this new behavior in Windows Insider builds by creating the following registry key and rebooting the device.  This key will be removed as Microsoft get closer to release.
HKLM\SOFTWARE\Microsoft\Security Center\Feature
DisableAvCheck (DWORD) = 1
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