I have the same question. If I reply from a received email (addressed to the HME account), can I reply from within Mail and will the person receiving it see only the HME email address? Using beta 6. Also wondering that if it works, would I have to reply using Monterey Mail or would it work replying in my normal Big Sur Mail? Really think this new feature and the Relay feature are a huge advantage for os12. Thus would like to be able to actually try it including the reply part. Thanks.

I think I have figured this out. When you receive an email response from someone you've sent a web enquiry form to using HME, you will notice that their return address has been coded so that if you reply to them, your reply now goes to icloud where it is handled. In other words, their coded email return address now ends with icloud.com and includes their actual email and a code. Thus I'm assuming when it goes to that coded icloud email address, it then gets your HME specified email address added as the sender.

Just in case you are not aware, at least the System Supplemental folder fonts can be disabled using the font manager Typeface. That doesn't resolve the problem of far too many system fonts still showing up in many apps, but it at least helps a little bit.

I've experienced a couple problems where the Private Relay in OS12 wouldn't activate and I ended up having to restart/reboot OS12 to get it to respond/work. But with a reboot, it worked. Doesn't happen every time I reboot, but 2-3 times. My config may contribute to the problem since I run OS12 beta within a Parallels 16 VM.