diff --git a/docs/config.md b/docs/config.md
index 14c125d..0c6f6fd 100644
--- a/docs/config.md
+++ b/docs/config.md
@@ -346,7 +346,7 @@ statuspage.io (though these days most services also support webhooks and HTTP ca
 To configure the SMTP server, you must at least set `smtp-server-listen` and `smtp-server-domain`:
 
 * `smtp-server-listen` defines the IP address and port the SMTP server will listen on, e.g. `:25` or `1.2.3.4:25`
-* `smtp-server-domain` is the e-mail domain, e.g. `ntfy.sh`
+* `smtp-server-domain` is the e-mail domain, e.g. `ntfy.sh` (must be identical to MX record, see below)
 * `smtp-server-addr-prefix` is an optional prefix for the e-mail addresses to prevent spam. If set to `ntfy-`, for instance,
   only e-mails to `ntfy-$topic@ntfy.sh` will be accepted. If this is not set, all emails to `$topic@ntfy.sh` will be
   accepted (which may obviously be a spam problem).
@@ -369,6 +369,42 @@ configured (in [Amazon Route 53](https://aws.amazon.com/route53/)):
   <figcaption>DNS records for incoming mail</figcaption>
 </figure>
 
+You can check if everything is working correctly by sending an email as raw SMTP via `nc`. Create a text file, e.g. 
+`email.txt`
+
+```
+EHLO example.com
+MAIL FROM: phil@example.com
+RCPT TO: ntfy-mytopic@ntfy.sh
+DATA
+Subject: Email for you
+Content-Type: text/plain; charset="UTF-8"
+
+Hello from 🇩🇪
+.
+```
+
+And then send the mail via `nc` like this. If you see any lines starting with `451`, those are errors from the 
+ntfy server. Read them carefully.
+
+```
+$ cat email.txt | nc -N ntfy.sh 25
+220 ntfy.sh ESMTP Service Ready
+250-Hello example.com
+...
+250 2.0.0 Roger, accepting mail from <phil@example.com>
+250 2.0.0 I'll make sure <ntfy-mytopic@ntfy.sh> gets this
+```
+
+As for the DNS setup, be sure to verify that `dig MX` and `dig A` are returning results similar to this:
+
+```
+$ dig MX ntfy.sh +short 
+10 mx1.ntfy.sh.
+$ dig A mx1.ntfy.sh +short 
+3.139.215.220
+```
+
 ## Behind a proxy (TLS, etc.)
 !!! warning
     If you are running ntfy behind a proxy, you must set the `behind-proxy` flag. Otherwise, all visitors are
diff --git a/docs/releases.md b/docs/releases.md
index d09dcd0..2de28bc 100644
--- a/docs/releases.md
+++ b/docs/releases.md
@@ -10,6 +10,7 @@ and the [ntfy Android app](https://github.com/binwiederhier/ntfy-android/release
 
 * Download attachments to cache folder ([#181](https://github.com/binwiederhier/ntfy/issues/181))
 * Regularly delete attachments for deleted notifications ([#142](https://github.com/binwiederhier/ntfy/issues/142))
+* Translations to different languages ([#188](https://github.com/binwiederhier/ntfy/issues/188), thanks to [@StoyanDimitrov](https://github.com/StoyanDimitrov))
 
 **Bugs:**
 
@@ -17,6 +18,11 @@ and the [ntfy Android app](https://github.com/binwiederhier/ntfy-android/release
 * SQLiteConstraintException: Crash during UP registration ([#185](https://github.com/binwiederhier/ntfy/issues/185))
 * Refresh preferences screen after settings import (#183, thanks to [@cmeis](https://github.com/cmeis) for reporting)
 
+**Translations:**
+
+* Bulgarian (thanks to [@StoyanDimitrov](https://github.com/StoyanDimitrov)) 
+* Spanish (thanks to [@rogeliodh](https://github.com/rogeliodh))
+
 **Thanks:**
 
 * Many thanks to [@cmeis](https://github.com/cmeis), [@Fallenbagel](https://github.com/Fallenbagel), [@Joeharrison94](https://github.com/Joeharrison94),
@@ -27,6 +33,11 @@ and the [ntfy Android app](https://github.com/binwiederhier/ntfy-android/release
 **Bugs:**
 
 * Do not allow comma in topic name in publish via GET endpoint (no ticket) 
+* Add "Access-Control-Allow-Origin: *" for attachments (no ticket, thanks to @FrameXX)
+
+**Documentation:**
+
+* Improved [e-mail publishing](config.md#e-mail-publishing) documentation
 
 -->