I am rendering notes with this CSS:

div.Note, div.Tip, div.Preview, div.Caution, div.CPPNote {
  border-top: 3px solid black;
  border-bottom: 1px solid black;
  box-decoration-break: slice;
  ...
}

Notes can be long, and they may need to be broken across pages.

The box-decoration-break is there so that borders and icons (rendered as background-image) don't get repeated when a note is broken across pages.

Unfortunately, sometimes border-bottom is rendered on the top of the next page.

That seems just wrong. Why would anyone want a lonely border on the top of the next page?

Do any of the boxes have a fixed height specified? Could you attach an example document demonstrating the problem?

See the top of page 53 of the PDF file for an example.

1. alice.zip‎ 345.7 kB