/usr/lib/ghc-doc/hoogle/algebra.txt is in libghc-algebra-doc 3.1-2build2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-algebra-doc/html/algebra.txt
/usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-algebra-doc/html/algebra.txt