$ which kwin /usr/bin/kwin $ dpkg -S usr/bin/kwin kwin-x11: /usr/bin/kwin kwin-x11: /usr/bin/kwin_x11
$ ls -l /usr/bin/kwin /usr/bin/kwin -> kwin_x11 $ dpkg --list kwin-x11 ii kwin-11 4:5.17.5-4 amd64 KDE window manager, X11 version $ kwin --version kwin: symbol lookup error: /lib/x86_64-linux-gnu/libkwin.so.5: undefined symbol: _ZN12ScreenLocker7KSldApp30greeterClientConnectionChangedEv $ sudo apt clean $ sudo apt install --reinstall kwin-x11 libkscreenlocker5 ... finishes with no errors ... $ kwin --version kwin: symbol lookup error: /lib/x86_64-linux-gnu/libkwin.so.5: undefined symbol: _ZN12ScreenLocker7KSldApp30greeterClientConnectionChangedEv $ objdump -T /lib/x86_64-linux-gnu/libkwin.so.5 | grep greeterClientConnectionChanged 0 DF *UND* 0 _ZN12ScreenLocker7KSldApp30greeterClientConnectionChangedEv $ dpkg -S lib/x86_64-linux-gnu/libkwin.so.5 kwin-common: /lib/x86_64-linux-gnu/libkwin.so.5.17.5 kwin-common: /lib/x86_64-linux-gnu/libkwin.so.5 $ dpkg --list kwin-common ii kwin-common 4:5.17.5-4 amd64 KDE window manager, common files $ sudo apt install --reinstall kwin-x11 libkscreenlocker5 kwin-common ... finishes with no errors ... $ kwin --version kwin: symbol lookup error: /lib/x86_64-linux-gnu/libkwin.so.5: undefined symbol: _ZN12ScreenLocker7KSldApp30greeterClientConnectionChangedEv
