Just to be complete here:
Bitwarden: Hard dependency on MS SQL Server (docker-image for this needs a lot of resources)
Vaultwarden (formerly bitwarden_rs): Defaults to using SQLite, but can use different databases
Only Bitwarden supports SSO.
Vaultwarden does not support SSO, as per the wiki, support will only be done when code is donated
Both of these support the same clients, which means the bitwarden mobile app can connect to self-hosted Vaultwarden.
I can’t integrate it into EGroupware (I currently lack the necessary skillset to add OpenID support), but it does tick all the other boxes for me.