@Ratha ITC im just guessing now but i would expect the UAC popup to show after you allow the smartscreen (chrome). Reason is maybe chrome tagged it with some fs metadata/attribute that it came from "untrusted zone" (i dont use any of those "security features" so i have no idea)
think we all should go back to 1909 and be happy ,with covid-19 who knows if this 2004 will be released
1903 Was in Release Preview long time last year. 2004 (Probably) Should be too. It should be release next month. You can see the release number : 2004 (now we at 20/03- march).
As far is i know, the defrag bug is just cosmetic. From the known issues on build 19541: "The Optimize Drives Control Panel is incorrectly reporting that optimization has never run on some devices. Optimization is completing successfully, even though it is not reflected in the UI." I think someone here mentioned that it was fixed in a later insider preview build (19551) anyway, so I'm sure a future CU will fix it. If not, well while annoying to look at, nothing but a UI bug.
I don't know. I know 2004 is in Release Preview ring and it can take a time like it was in 1903. MS can add a new CU to 2004 before it will release to public.