I’m working on cleaning up about 3000 topics that were imported from our mailman archive. We dumped them into an archive category, with the plan of cleaning up and moving into appropriate categories as time allows. I jumped right in with merging some topics (some threads came in as multiple Discourse topics) and moving them to the appropriate category.
The act of merging appears to trigger an email to all users on mailing list mode, just as if it were a new post (the date on the post is the correct, old date). I can’t really think of a reason why someone would want that.
In our test instance, we muted an entire category, and seem to be able to merge topics in that category without triggering the emails. Are there any other actions or situations that are likely to cause these old posts to appear as new, and get mailed out to all users who are receiving new posts?