Re:MS to Give Windows 10 a ‘Modern’ Overhaul with Light Weig...
by dragonwriter on Monday January 29, 2018 @01:43PM
(#16259611)
Here's an article which discusses the strategy in some more detail, explicitly identifying Polaris as the composer (but then also seeming to use it as the name for a desktop spin of Windows with Polaris in the stack):
https://www.windowscentral.com/windows-core-polaris
This Windows Central article actually seems to be the source for most of the other recent coverage, so it may be the most complete piece out there.
It makes sense that there would be a codename for the desktop-composer on top of CShell, and that would be a far better explanation of things than the article here.