Unfortunately we have had to remove opera and the desktop OwnCloud client (which can be used to access our ChemBox service) from our managed Ubuntu 16.04 workstations. The 3rd party repositories we use for installing these pieces of software no longer support Ubuntu 16.04.
Both packages still work fine on Ubuntu 18.04: if you use a departmentally-managed 16.04 computer and want to arrange an upgrade, please let us know.