/usr/lib/ghc-doc/hoogle/HGL.txt is in libghc-hgl-doc 3.2.0.2-2build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-hgl-doc/html/HGL.txt
/usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-hgl-doc/html/HGL.txt