/usr/lib/x86_64-linux-gnu/libnomacsGui.so.3 is in libnomacsgui3 3.4.1+dfsg-5.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libnomacsGui.so.3.4.0
/usr/lib/x86_64-linux-gnu/libnomacsGui.so.3.4.0