This file is indexed.

/usr/lib/x86_64-linux-gnu/libfftw3l_threads.so.3 is in libfftw3-long3 3.3.5-3.

This file is owned by root:root, with mode 0o777.

It is a symlink to /usr/lib/x86_64-linux-gnu/libfftw3l_threads.so.3.5.5