The KeePass ecosystem has gotten a little bit better. It's still not exactly seamless. File sync across all of Windows, Linux, macOS, iOS and Android seems to involve either proprietary user-hostile sync tools or dealing with lots of jank.
As far as I can tell, the only competitor with a similar feature set that even claims to be open-source is Proton Pass. But I can't find any information on whether the server side can be self-hosted.
As far as I can tell, the only competitor with a similar feature set that even claims to be open-source is Proton Pass. But I can't find any information on whether the server side can be self-hosted.