If interaction is active (\setupinteraction[state=start]), then
these page numbers will be hyperlinks back to the citations. If
numbering=yes, then the numbered bibliography entries will also
contain hyperlinks back to the first occurrence in the text where
the entry is cited (which is the same as the first page indexed).
However, that does not seem to be the case, either in my own documents
or in that manual, which clearly has interaction enabled for other items.
Is the manual incorrect, or is this a bug?
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