Add footnotes and extra info to mail page

content/mail.md

@@ -27,11 +27,11 @@ some of the main features.
 ### Spam and Malware Scanning
 
 Mailcow uses [Rspamd](https://www.rspamd.com/) for spam filtering, virus
-detection (via [ClamAV](https://www.clamav.net/)), and DKIM signing.
+detection (via [ClamAV](https://www.clamav.net/)), and DKIM signing.[^1]
 
 #### Greylisting
 
-Emails that could possibly be spam (7+ points) are
+Emails that could possibly be spam (7+ points[^2]) are
 [greylisted](https://en.wikipedia.org/wiki/Greylisting_(email)) (otherwise known
 as a soft reject). This means that at first, the message is temporarily
 rejected. Legitimate email servers will keep track of this and try again
@@ -43,7 +43,7 @@ to the Junk folder instead of Inbox.
 
 Rspamd will automatically learn an email as spam (or ham) if you move it into
 your Junk folder from any other folder except Trash. It will also automatically
-learn using emails that get an extremely high or extremely low score.
+learn using emails that get an extremely high or extremely low score.[^3]
 
 ### bobamail ui
 
@@ -56,11 +56,32 @@ which allows you to view your emails.
 You can create temporary aliases (otherwise known as spam aliases) in the
 [bobamail ui](https://mail.boba.best/). These aliases can be created for time
 periods varying from one hour to four weeks. Temporary aliases can be created
-and deleted at any time.
+and deleted at any time.[^4]
+
+#### Plus Aliases and Tagging
+
+Mailcow supports "tagging" your email address using the plus sign. For example,
+mail sent to example+shopping@boba.best and example+work@boba.best will both go
+to example@boba.best. Anything can be put after the plus sign, as long as it
+makes a valid email address. In [bobamail ui](https://mail.boba.best), under the
+"Set handling for tagged mail" section, you can choose what to do with mail sent
+to these addresses. You can choose to either:[^5]
+
+- do nothing, and send the email to your Inbox
+- add the tag to the subject (ex. `[shopping] New deals`)
+- move the mail to a subfolder under Inbox (ex. Inbox/shopping)
 
 ### Webmail Client
 
 Mailcow provides a webmail interface using [SOGo](https://www.sogo.nu/). It
 provides an easy-to-use web-based mail client in case you don't want to use one
-on your computer. This is separate from [bobamail ui](https://mail.boba.best/),
+on your computer. In addition, SOGo provides an address book and calendar.[^6]
-which is Mailcow's UI, for changing various settings.
+SOGo is separate from [bobamail ui](https://mail.boba.best/), which is Mailcow's
+UI, for changing various settings.
+
+[^1]: https://mailcow.github.io/mailcow-dockerized-docs/u_e-rspamd/
+[^2]: https://mailcow.github.io/mailcow-dockerized-docs/u_e-rspamd/#spam-filter-thresholds-global
+[^3]: https://mailcow.github.io/mailcow-dockerized-docs/u_e-rspamd/#learn-spam-ham
+[^4]: https://mailcow.github.io/mailcow-dockerized-docs/u_e-mailcow_ui-spamalias/
+[^5]: https://mailcow.github.io/mailcow-dockerized-docs/u_e-mailcow_ui-tagging/
+[^6]: https://mailcow.github.io/mailcow-dockerized-docs/u_e-sogo/