Reopening as 21043 and 20741 don't seem to have fixed every use cases.

 
Steps to reproduce

1. Edit a page
2. Insert a large table (e.g. with 10 columns and 24 rows) with some data content, or use the XAR attached to reproduce it easier
3. Export the page as PDF keeping the default PDF Export options ticked (Cover, Table of Contents, Header, Footer)
4. In the exported PDF, observe the data from the first rows where a new page begins (page 6 in the provided xar)

Expected results

The data is the same on both the XWiki page and the exported PDF file.

Actual results

Some data is missing from the first row when a new page begins on the exported PDF file, see the attached screenshots.