/usr/lib/x86_64-linux-gnu/librest-extras-0.7.so is in librest-extras-dev 0.7.93-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/librest-extras-0.7.so.0.0.0
/usr/lib/x86_64-linux-gnu/librest-extras-0.7.so.0.0.0