Just so I understand you correctly, are you saying that you’re getting somethign like this:
| this is supposed to represent the |
| last verse of text. |
| |
| The Book of Job |
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If so, then we’ll need an archive (see the help tab), because that should never happen.
There should only be a single horizontal line between books. It is actually a line separating double and single column text. I got that far digging a couple of weeks ago, but I’m not entirely sure why it started getting triggered twice a few months ago, and haven’t had time to dig into it further.
At the moment there’s no way to turn it off, other than not beginning the new book on the last page of the old one.