Sorry, I didn't see the reply, I thought I would have a notification. These activities use box2d and according to the logs ( https://buildd.debian.org/status/fetch.php?pkg=gcompris-qt&arch=alpha&ver=0.95-1&stamp=1547387638&raw=0) it is disabled and we don't add them in the package on this case ("Disabling qml-box2d module and depending activities: balancebox,land_safe,submarine").
This means that, even if box2d is installed afterwards, these activities won't be present. I created a new task on GCompris bug server to check if it is possible to have the box2d check at runtime instead of compilation time: https://phabricator.kde.org/T10432 On Debian side, it seems the qml-box2d library is not packaged ( https://github.com/qml-box2d/qml-box2d). In GCompris, when it's not available we compile it ourselves (via -DQML_BOX2D_MODULE=submodule) but I'm not sure if it would be acceptable to do it in Debian? Best way would probably be for qml-box2d to be packaged, set it as a mandatory dependency and use -DQML_BOX2D_MODULE=system. Note: I'm one of the GCompris developers, I don't know much about the packaging. Johnny
