/usr/share/hunspell/de_AT.aff is in hunspell-de-at-frami 1:4.2.1-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/hunspell/de_AT_frami.aff
/usr/share/hunspell/de_AT_frami.aff