In NR 3.2.6 (version 2.21.5) a new formatting for the table of contents
is described. The documentation suggests the formatting, which defaults
of bold, will only be applied in the case of a hierarchical table of
contents, whereas the bold formatting is applied also for a flat table
of contents. The previous behaviour can be restored by adding
tocFormatMarkup = #make-normal-text-markup. I am unsure if the
documentation is unclear or the new behaviour is not as intended.
How the table’s top level entries will be formatted (if there are
several hierarchical levels). This is actually a procedure, as explained
in Markup construction in Scheme.