Get rid of unnumbered sections that need to be referenced

[cabo]

Specifically,

{{comparisons}} in {{filter-selector}} {{syntax-index}} {{index-semantics}} {{extest}}

[glyn]

Do you propose to delete these headings and the references, add numbers to these headings, or what?

[cabo]

Use unnumbered sections only where this is simple internal structure. As soon as sections are referenced, this is no longer the case.

[glyn]

May I leave this change to you? Assigning it to you for clarity.