If the bundle contains an origin link we can now install related
things from it, such as locale data.
You can also build the bundle with --runtime-repo=URL, where the url
points to a flatpakrepo file for a repo with runtimes. This works
similar to the RuntimeRepo= feature in flatpakref files.
This lets any client, possibly in a sandbox if it has access to the
session helper, spawn a process on the host, outside any sandbox.
Clearly this is not something you typically want a sandboxed app to
do. However, it is sometimes very useful when using flatpak mainly
for distribution. For instance, an IDE needs to use this to launch a
flatpak build operation inside the sandbox. (Because otherwise recursive
calls to flatpak will not work.)
Alexander Larsson