Comment 15 for bug 1552792

More information from Julian Klode (https://github.com/hughsie/PackageKit/issues/201#issuecomment-364363222):

"Sure, it's an option given to backends, see pk_backend_remove_packages() - it's a parameter in the Dbus API's RemovePackages() method. In the client API, you can specify it as a boolean parameter for pk_client_remove_packages_async.

But it's not the kind of autoremove that would be correct for gnome-software - gnome-software needs to remove "new garbage", that is only packages that become unused as a result of the removal and not any other unrelated garbage that has accumulated over time."