/usr/share/help/sr/ubuntu-help/index.page is in ubuntu-docs 16.04.3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/help/sr/ubuntu-help/../../../help-langpack/sr/ubuntu-help/index.page
/usr/share/help/sr/ubuntu-help/../../../help-langpack/sr/ubuntu-help/index.page