This is one of those bugs that is easier to show, so I am attaching a GIF.
The GIF only showcases a small amount of text, but it's really: any remaining part of a document after a horizontal rule, small or large, no longer renders properly (until the horizontal rule is removed).
I am on macOS 10.14.6 and NP 13.10.1. This issue started for me with NP 13.10.0.