Index entry fo:block disrupts keep-with-next.within-column

[Peter Desjardins <peter.desjardins.us@gmail.com>]

I noticed a section title separated from the first paragraph in its
section by a PDF page break. The title of the section is at the bottom
of one page and the first paragraph at the top of the next page. I'm
using the docbook-xsl-ns-1.78.1 stylesheets.

The problem is caused by an index entry between the title and the
first paragraph. If I remove the index entry, the title is kept-with
the following para.

The index entry results in a fo:block to mark the internal destination:

  <fo:block id="d0e240"><!--containers--></fo:block>

So the title is satisfied with being kept-with the index entry fo:block.

I am considering customizing the fo:block for index entries to add a
keep-with-next.within-column="always" attribute.

Does anyone know of a better way to prevent index entries from
interfering with keep-with-next behavior?

Thanks!

Peter

****** My DocBook *****

<section xml:id="containers-about">
  <title>Containers</title>

  <indexterm>
    <primary>containers</primary>
   </indexterm>

   <para>Containers ...


****** The corresponding FO *****

<fo:block>
      <fo:block keep-together.within-column="always" margin-left="0pt"
font-family="sans-serif,Symbol,ZapfDingbats">
        <fo:block keep-with-next.within-column="always">
          <fo:block font-family="sans-serif,Symbol,ZapfDingbats"
font-weight="bold" keep-with-next.within-column="always"
space-before.minimum="0.8em" space-before.optimum="1.0em"
space-before.maximum="1.2em" text-align="start" start-indent="0pt">
            <fo:block font-size="12pt" color="#405D99"
font-weight="600" space-before.optimum="2.0em"
space-before.minimum="1.8em"
space-before.maximum="2.2em">Containers</fo:block>
          </fo:block>
        </fo:block>
      </fo:block>
    </fo:block>
  </fo:block>
  <fo:block id="d0e240"><!--containers--></fo:block>
  <fo:block space-before.optimum="1.7em" space-before.minimum="1.5em"
space-before.maximum="1.9em">
    Containers ...