I am running a defederated local Matrix server, and I need to set up calls. From what I can tell, the "legacy" calls require a STUN and TURN server, and the new MatrixRTC standard seems to require them as well for Livekit to work. However, I do not want to expose anything out to the public internet, as I want everything to be behind NAT for local access only (all of the clients for the server will also be behind the NATted network). I also have Tailscale running on my servers, and it would be useful if I would be able to connect to the TURN server even when not in the network. Is there a way to get STUN/TURN to work in this situation? It seems that all the servers expect to have public network access.

I need to run my own email server for some of my domains, because the providers that I usually use don't support them (they use Unicode characters, and not everyone supports that yet). I have a small VPS that I run a few Docker containers on, and I'm wanting to try and run an email server on it as well. What containers are good for a low-hassle email setup? I don't need a mailbox webui (ex: roundcube), but it would be nice to have a UI for management. I do need multi-domain support, however.

EDIT: For anyone wondering, I decided to go with Mailu. Stalwart didn't play will with internationalized domains (although it was the only server to support EAI/SMTPUTF8), and Mailcow would have been a bit more difficult for me to change to bind mounts and reconfigure Docker networking with.

I live in Canada, and I am figuring out a way to get a "registered" phone number from a cell company just for SMS verification texts. However, I am wanting to find out if there is a service that would do the same thing (and potentially cheaper: the lowest plan I found from a carrier is CAD$15/mo). I would be using it just for SMS verification texts (WhatsApp, Telegram, etc.).

I have been reading about the new OIDC system (since Element now has a QR code login). I can't seem to understand the purpose of it, as it seems that Matrix already has all of the features wanted, but more simple. Why would there need to be a new OIDC system, if signing in with services with Google or GitHub is already supported and configurable per homeserver? Why would regular user+password login need to be reimplemented, but now require a website to login instead of being able to login through something like a terminal?

Firefox's Reader View seems to me to show a font that is similar to Helvetica. If I try to make it use only Inter, Arial, or "sans-serif", then it changes the font. What font is Firefox using instead? This also happens in Firefox forks.

I'm looking at some old Intel and Pentium CPUs that are in a NUC. Are cores and max clock speed the only things that matter? Would a Pentium be good enough to run Immich? I have a i7-4790, and the NUCs I'm looking at range from a Pentium J5005 to a i3-1115G4. I do run Docker, does that affect anything?

I am wondering if an ISP or network admin on my network would be able to change where a DNS server is located at (ex: if a DNS server is located at 132.192.175.210, the ISP/netadmin can redirect it to their own server at 11.29.102.201 to change where the DNS records point to). Does DNSSEC and DoH/DoT combat this, and how? Why is it safe to use a domain for DoH/DoT if it requires going through insecure DNS to get to a secure DNS?

I am running Fedora Server with Docker installed, and it has a folder that connects to my NAS via SMB. I will have all of my Docker files (and Compose configs) stored on my NAS, since it has a lot more storage. I am worried that Docker will glitch out and cause a mess, since my NAS starts ~2 minutes later than my server from a reboot. Is there something that I can do to make sure Docker is able to connect to the SMB share safely?