Earlier quoted context omitted.
For self-host, use Vaultwarden [1] [1] https://github.com/dani-garcia/vaultwarden
If you do self-host, please consider still buying premium from Bitwarden. It's only $10 per year. It's well worth the money and since you're still using the clients, which are still developed Bitwarden, it'll help towards keeping the product alive.
Agreed, I'm doing the same. I used the TOTP feature before I self-hosted.