Comment 5 for bug 1404494

From Ubuntu 15.10 onwards, libdvd-pkg is available to ease the installation of libdvdcss.

    Install the libdvd-pkg package (no need to add third party repositories) via Synaptic or command line:

sudo apt-get install libdvd-pkg

    Follow libdvd-pkg's instructions to let it download, compile, and install libdvdcss.