Got it a little while ago.

It's a security update for Edge, no restart required.

Microsoft Security TechCenter said:

Microsoft Edge (3211320) (Critical)

Microsoft Security Bulletin Summary for January 2017

Getting it now. Thanks.

On 11 Jan 17, I got update no.KB3213986. Now it is KB3211320. Why number is backward? OS Build still remains 14393.693.

Bree said:

It's a security update for Edge, no restart required.

Microsoft Security Bulletin Summary for January 2017

That security bulletin you linked to says that the update "requires a restart". My PC doesn't indicate that a restart is needed. But I'll do so, just to be safe.

AllenChicago said:

That security bulletin you linked to says that the update "requires a restart". My PC doesn't indicate that a restart is needed. But I'll do so, just to be safe.

So it does, I guess they mean Edge has to be closed and restarted before it takes effect. My PC didn't ask for a restart either.

Just for info : the above Bulletin link refers to KB3210720 dd 01/06/2017 ...
As for KB3211320, no changelog is available up to now.

Just installed, no restart required. :)