/usr/lib/ghc-doc/hoogle/MissingH.txt is in libghc-missingh-doc 1.2.0.0-3build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-missingh-doc/html/MissingH.txt