@music2myear the computer was initially not on a domain, and then I added it to a domain. same behaviour before and after.

@john a password is only required when remote, not when local - I can attach to another user's session without password, so long as I'm sitting at the console.

I don't consider this to be a good answer; I think it's only adequate (so I'm not going to mark it as the accepted answer, at least not for a while). It's possible that there might actually not be a good answer; I've skimmed the Chromium source code, and the IsOS hack is the best I found.

Chrome engages in a number of questionable privacy related actions - some are network related, such as reporting "metrics". Others are more invasive, like the software reporter tool or chrome cleanup. I want to disable these things, but the policy only works if your computer is in an Active Directory, and I don't have one of those.