I set it up in a couple of minutes using Docker-compose with Traefik. I love that Bitwarden has clients and plugins everywhere (FF and iOS being most relevant to me) and I can self-host. The sweetspot for me. I have had too many conflicts with my KeepassXC database on Nextcloud in the past, time for a solution with integrated sync.

Btw the "custom server" setting is a bit hidden, it is behind the cogwheel in the upper left in most cases.