/usr/share/man/man3/unicode::linebreak_iter.3.gz is in libcourier-unicode-dev 1.4-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man3/unicode::linebreak_callback_base.3.gz
/usr/share/man/man3/unicode::linebreak_callback_base.3.gz