Install usrmerge by entering the following commands in the terminal:
sudo apt update sudo apt install usrmerge
Description:
Convert the system to the merged /usr directories scheme
This package will automatically convert the system to the merged /usr directory scheme, in which the /{bin,sbin,lib}/ directories are symlinked to their counterparts in /usr/. . There is no automatic method to restore the precedent configuration, so there is no going back once this package has been installed.
Homepage: https://wiki.debian.org/UsrMerge
Version: 17
Section: universe/admin