[Avamander]

The infuriating part is that one can't reply from the address it was sent to, only from the one that's primary.

[0xCMP]

Yes, in fact this is one of the more annoying parts of this feature. When you're doing a support thing you usually have to reply with the exact same email. In my Google Suite account I have many domains setup to a single account and often times a reply uses my main account instead of an alias+domain I've setup on the account which received the email.

Would be nice to be able to easily reply as any of those combinations and default to the one it was sent to (dots, +'s, and domain).