Vaultwarden is an unofficial server compatible with Bitwarden clients. A replacement must preserve the data and recovery workflow your users depend on, not merely accept a login.
In a disposable test vault, create passwords, notes, collections, shared items, and an account with two-factor authentication. Export and import a non-sensitive sample, then verify item counts, URLs, attachments, organization access, and client sync on desktop and mobile. Disconnect the server briefly and confirm what remains available offline. Finally restore a backup on a separate instance and rotate a test credential.
The Vaultwarden project describes its compatibility scope. Never use a real vault export as an unencrypted test file. Keep the old server and a verified backup until every client has synchronized successfully.
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