/usr/share/doc/libharfbuzz-doc/html is in libharfbuzz-doc 1.7.2-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libharfbuzz-doc/../../gtk-doc/html/harfbuzz
/usr/share/doc/libharfbuzz-doc/../../gtk-doc/html/harfbuzz