Attached is a top-up patch with a few small fixups.
I suggest to wait for the resolution of the "Replication/backup defaults" thread. I would not want to be in a situation where users who have not been trained to use replication slots now have yet another restart-only parameter to set before they can take a backup.
Thanks for the review and the top-up patch. I've applied it and pushed.
I just realized I missed crediting you with the review and the top-up in the commit message. My apologies for this.