If you got the automatic updates on the bitwarden clients, they will show an empty vault if you are selfhosting vaultwarden.
It seems to be an accidental bug in the bitwarden clients that are assuming that they’re talking with official servers
It’s fixed with the latest release of the vaultwarden server that was published a few minutes ago
Keyguard. It’s not perfect and makes money from the paid version for syncing changes back to the server as well as offline editing that will then sync when you’re back online. But it was worth it back when I bought it, and it has never broken so far.