I think yesterday it was on the front page at the #2 spot, and now it's totally disappeared. Was this just a normal algorithm or timing thing, or was it manually removed? I wonder if it was manual because another post of mine was on the front page with far fewer upvotes, and it was posted on the same day, though it remains on the front page while this other post is gone. But of course, it could well be some automatic thing that I don't understand the mechanism of. If it was manually removed, why?
Your post shouldn't have started on the front page, because all posts start out in the "personal blog" category by default, which is only viewable from "All Posts". Some posts are then classified either as "frontpage" (shows up on the front page) or "community" (shows up on the community page). Because your post was about community discussion norms, it was a better fit for the "community" category.
If posts that haven't been categorized are showing up on the front page, something unexpected is happening with our code -- do you happen to have a screenshot of this? Or is it possible that you were viewing the "All Posts" page?
(People with questions about moderation // Forum features are also welcome to PM me on the Forum or email me directly.)
Meta-note: This post will stay in the "personal blog" category, because that's what we generally use for questions with a single "correct" answer, especially if they are questions about how the Forum works. See here for more on categorization.
I think it was re-classified as 'Community', which removes it from the front page and puts it in a secondary location. People can still see it but they have to have 'Include Community Posts' ticked, which I think is unchecked by default.