Either a local SMTP server (less used) or an external service (more common). The SMTP is configurable but I believe most used option is ssl smtp over port 587.

nominative determinism

I mean so is control d a set and forget. Even more so because they manage any changes and workarounds the companies come up with. Its basically designed for this. Having tried both options its my preferred option.

Yes I do use opnsense and it was more annoying than control d. I tried both options.

One way I have reduced my subscriptions is by using control d. I know vpns are popular on lemmy but I found it an annoying to have to have a vpn for each device I wanted to bypass a country lock. Moreover it was annoyyng for some devices like apple tv that does not support a vpn. Establishing a vpn on the firewall broke other services that I needed to work locally in my country.

Control d on the other hand is a dns proxy tunnel so you just alter the dns on the devices you want to use it, and in their control panel you can have different countries per service - so if you browse youtube that can go via a country that does not allow ads. Bbc iplayer can be told to go via uk and so on. This is a lot more convenient and allows you to retain your country for all services except the ones you want to tunnel.

I read this whole thread and didnt find a single person who uses teams inside ferdium like me.

The password manager for iphone or ios has mfa built in - seems to work ok. Its a bit annoying if you use a desktop thats not mac though and have to search for the mfa code among the millions of passwords.