The `foot' link and destination groups include the
\numberedfootnote and
\footnote macros (see Footnotes). The `footback' groups
include the same macros, but control parameters for links and
destinations created inside the footnote to point back to the footnote
mark within the text body.
The macros use hyperlink labels generated by
\hlfootlabel and
\hlfootbacklabel. The default formats for the labels are
‘FOOTnumber’ and ‘FOOTBnumber’, respectively,
where number is the value of the count register
\hlfootlabelnumber. This register is incremented at every
footnote.
Generally, footnote hyperlinks are not of much use, because the footnotes are usually placed on the same page as the footnote mark. Therefore, footnote hyperlinks are disabled by default. Here is how you can turn them on selectively, without affecting the other kinds of hyperlinks (see Turning hyperlinks on/off for a group):
\hldeston[foot,footback]
\hlon[foot,footback]