h i see. then maybe put a hardened freebsd and vaultwarden on it with a kill switch?

Yeah, instead of putting a kill-switch, you can just use a hardened FreeBSD or OpenBSD to host your Vaultwarden and make it only accessible within your private home network so that it doesn’t leak information outside, which is something i planned for, never did. But it is definitely on my list of things for this month, to move the DB from my hoster to my local lan, to move more stuff out of the cloud alas, someone else's computer.