Comment 3 for bug 1638362

To be precise, extra packages could be specified in the following ways.

(1) through a file specified as an argument to a switch on the libertine-container-manager command line, said file containing one package name per line

(2) through an entry in a (new, optional) configuration file ${XDG_CONFIG_HOME}/libertine

Installation of these extra user-specified packages would take place in a phase after the container is created. Errors in installation are reported and ignored so that processing of the list can continue until the end is reached.