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Microsoft to test “new features and more” for aging, stubbornly popular Windows 10
(arstechnica.com)
This is a most excellent place for technology news and articles.
Is one of those "features" CoPilot? Because I did a search for it on my Windows 10 installation, and found several small bits of it, including a directory called "Microsoft CoPilot." It looks like a placeholder for a full installation, later on. I'm guessing Office 365 put it there.