Any topic that is not indexed, not in the TOC and not linked
from other topics etc can only be accessed by searching. However
the search will catch all text rather than just a keyword.
There are threads here describing how to exclude topics from
a search. How about excluding the topic from a search but making
the topic accessible by some hidden means in another topic. For
example, create a small icon the same colour as the background of a
page so that it cannot be seen. Make that a hyperlink to the topic.
I accept it is a kludge but it is only for a small number of people
in the know as to where that graphic is, it would work.
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