/usr/lib/x86_64-linux-gnu/libmatedict.so is in libmatedict-dev 1.20.0-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libmatedict.so.6.0.7
/usr/lib/x86_64-linux-gnu/libmatedict.so.6.0.7