/usr/share/doc/libglade2-dev/README is in libglade2-dev 1:2.6.4-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libglade2-dev/../libglade2-0/README
/usr/share/doc/libglade2-dev/../libglade2-0/README