How?
- Make a new topic
- Add a mailinglist tag
- Create the topic
- Close it
- Pin it
- Anyone can then watch the topic
- You post replies to the closed topic
Ordinary users cannot reply to the topic, so everyone who is watching it won’t get unnecessary spam.
However, it can be a good idea to put a warning on the end of updates:
“DO NOT REPLY TO THIS EMAIL. Doing so can generate a reply on the forum, which will then be sent to everyone watching this topic”
Why?
You can effectively create targeted mailing lists for very specific topics, or shared work or projects. Others in the community can discover this activity and start watching the topic to keep up to date, and also read previous announcements and information to get up to speed with the work.
Limitations
This only works for Trust Level 4 users, moderators and admins. If you need this capability then message the admins group and ask for your Trust Level to be set to 4. This also means any such users can reply to your topic. They’re an elevated trust level so they should know what to do, but everyone can make mistakes. Please be very careful when you reply to an Announce topic.
Replying to any notification from the a topic on the forum will post to that topic on the forum. This is a feature: the forum can be used entirely by email. But it does mean that any user with sufficient permissions to reply to your topic can also spam the mailing list by replying to an email from the mailing list. Hence the recommendation above to put a warning when adding updates to a mailing list topic.
If people turn off their email notifications and don’t visit the forum they won’t see the information. I guess they didn’t really want to follow the topic after all if they do this.
Other community members can’t ask questions about the topic in the topic, so best to make the first post as informative as possible: explain the purpose of the post, who it is for, how it operates (who updates it and approximately how often).
When you pin a topic a preview is displayed under the topic in the topic list view:
By default it grabs a fixed amount of text from the post, strips out all the formatting and uses this as the preview. You can control what is used for the preview by using an html element, e.g. in this post it looks like:
<div class="excerpt">How (and why) topics can be used like mailing lists.</div>