/usr/lib/x86_64-linux-gnu/libkdecorations2.so is in libkdecorations2-dev 4:5.8.4-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libkdecorations2.so.5
/usr/lib/x86_64-linux-gnu/libkdecorations2.so.5