/usr/lib/ghc-doc/hoogle/gtk-traymanager.txt is in libghc-gtk-traymanager-doc 0.1.3-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-gtk-traymanager-doc/html/gtk-traymanager.txt