Rated 5 out of 5 stars

Gmail側で「他のメール アドレスを追加」をしないといけないのが面倒だが、それ以外は楽になります。

Αυτή η αξιολόγηση γράφτηκε για παλιότερη έκδοση του πρόσθετου (1.0.2). 

Rated 1 out of 5 stars

Does not work. Assumes that aliases will have + signs in them or something.
If you want to be fancy, just add a regex field.
But that's not even necessary.
Just compare the domain the email was received at with my identity's domain, if it's the same, use the recipient's address.

Αυτή η αξιολόγηση γράφτηκε για παλιότερη έκδοση του πρόσθετου (1.0.2). 

Thanks for the feedback — at the time you reviewed, you were right: the extension only handled plus-addressing (user+alias@domain.com), so aliases on your own domain simply didn't match.

That's since been fixed. Newer versions add two more alias methods you can pick per account in the settings:

- Own domain — alias@yourdomain.com
- Catchall — anything@yourdomain.com

Both do exactly what you described: they compare the domain the mail was delivered to against your identity's domain, and if it matches, reply from the recipient's address — no + required. It also reads the delivery headers (X-Original-To / Delivered-To), so it still finds the right alias even when it wasn't in the To/CC line.

One thing to note: the feature is opt-in per account and defaults to plus-addressing, so you'll need to open the extension's settings once and select "Own domain" or "Catchall" for your account.

If you get a chance to try it again, I'd be glad to hear whether it works for your setup now.