/usr/lib/ghc-doc/hoogle/libghc-cabal-file-th-doc.txt is in libghc-cabal-file-th-doc 0.2.3-8.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-cabal-file-th-doc/html/cabal-file-th.txt