Mailbox uses Open-xchange, but the user most likely has nextcloud selfhosted.

I must admit, for a second I actually thought someone on earth was dumb enough to burn a billion tokens on this task.

Users successfully reverse-engineered Blender and published it as an open source project called BlenderCraft

You did what?

I doubt a DNS filter would noticeably increase CPU usage. We’re not talking about deep packet inspection here.

Such bugs have already appeared in the past. It’s only logical that this happens from time to time, as the creators of bitwarden don’t test the compatobility with 3rd party servers.

What is important is that they’re not deliberately blocking vaultwarden.

Even then, there are lots of edge cases with e-mail that are easy to get wrong and might become security risks.

I‘m not saying this applies to this project, this is more of a general concern.

The latest open weights model from google might be a good fit for you. The 26B model works pretty well on my machine, though the performance isn’t great (6 tokens per second, CPU only).

Maybe try some TLS-based VPN? This should work almost anywhere, because it looks like a standard HTTPS connection.

Wireguard - even on port 443 - is special as it uses UDP protocol and not the more widely used TCP protocol.