/usr/lib/ghc-doc/hoogle/colour.txt is in libghc-colour-doc 2.3.3-4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-colour-doc/html/colour.txt
/usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-colour-doc/html/colour.txt