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> Set that up about ten months ago now (don't remember exactly). It's working flawlessly. Not a single issue.
So now your laptop hasn't had security updates for 10 months? Things like this are part of the reason I did the research in https://dgl.cx/2023/09/ansi-terminal-security.
It also funny that you've reinvented basically a serial console, but in a modern way, with a second factor. (You could actually just use a physical terminal with S/Key or something.)
> P.S: it's just a proof of concept... But I think that requiring to tap a Yubikey every single time you want to do something as root is something that should be envisaged/discussed more and it was great to read TFA doing it too.
Agreed, https://neilzone.co.uk/2022/11/using-a-yubikey-or-other-secu... is another potential option for this.