/usr/lib/ghc-doc/hoogle/fb.txt is in libghc-fb-doc 1.0.1-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-fb-doc/html/fb.txt
/usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-fb-doc/html/fb.txt