It’s certainly not the same thing, but for a very weird unexpected imaging system, have a look at Ghost Imaging
Yeah, one of the more annoying “features” of Discourse is that even when the post that bumped a thread is deleted, the thread doesn’t un-bump. In fact, even when the bumping post is never even visible to the public at all, because it was caught for review by the automatic spam-catcher (as in this case), it still bumps the thread. I’m sure that the makers of Discourse would tell us that there’s some very good and important reason why that must be the way that a message board should work.
Why do spammers use old threads?