/usr/lib/libxcb-ewmh.so is in libxcb-ewmh1-dev 0.3.8-1build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/libxcb-ewmh.so.1.0.0
/usr/lib/libxcb-ewmh.so.1.0.0