better page breaking in PDF file from old prepped input

[alicerusso]

Description

• Input: https://www.rfc-editor.org/rfc/rfc8743.xml (which contains prepTime="2020-03-25T11:38:08")
• Output (with xml2rfc 3.15.3): https://www.rfc-editor.org/v3test/test8743.pdf

There are 6 extraneous page breaks within the Table of Contents, as compared with the PDF file generated by xml2rfc 2.41.0 (https://www.rfc-editor.org/rfc/rfc8743.pdf).

Seems the many instances of keepWithNext="true" inserted by the preptool yield the extra page breaks -- 159 instances of keepWithNext in the input file. Perhaps xml2rfc could yield better page breaks despite the extraneous keepWithNexts.

Code of Conduct

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[kesara]

This issue can be fixed by removing keepWithNext="true" in the Table of Contents (ToC). preptool doesn't seem to add keepWithNext="true" to ToC anymore, so can xml2rfc ignore any keepWithNext="true" attributes in ToC?

[alicerusso]

Similar issue w/ PDF output when input is: https://www.rfc-editor.org/rfc/rfc8656.xml (contains 97 keepWithNexts)

Most ToCs (in lower than 8775) aren't so long as to run into this issue.

Re:

preptool doesn't seem to add keepWithNext="true" to ToC anymore

Hm, looks like 3 instances of keepWithNext="true" in TOC of each prepped XML file (from about 8775 onward), e.g. rfc9303.xml.

so can xml2rfc ignore any keepWithNext="true" attributes in ToC?

Guessing those 3 are intended to help the first lines of the ToC appear on the same page.