At commit cfc1ce28054d64d26808545fa5e69660a234c530, I do not have a visible banner topic anymore. The topic remains pinned but I don’t have the option to unpin it since ‘banner topic’ does not appear anymore:
The problem is that the topic is in a private category
Can no longer create global banners from restricted categories
Can you move the topic to a public category and unlist it? Or create a new topic in a public category and make that a banner?
@Moin you’re following me around with great answers 
Yeah, I know
This is because I posted to the wrong place, so I trashed the original, and pasted it here. Duh.
I know this is not as easy as it used to be, but after discussing, you could split the first post into a new topic or delete the replies, so users won’t see them. To hide the edits on the first post, you could hide all the revisions so they are only visible for staff. Scheduling topics for future publication might be easier because it removes all the edits before moving the topic.
I don’t think there is a solution that removes replies and edits at once.
I think the best course of action is to unlist and mute the banner topics, and indeed, use linked topics for staff.
Actually, I’m wondering whether the banner topics would work in a public, but muted category. That would solve all issues, since most of the time nobody wants to hear about the background work of community-related actions, but still might be interested – e.g., if they want to become an active host.
Yes! You can use a globally muted public category for banners.