The background apps menu currently tracks instances rather than
apps. That matches the behavior of `flatpak ps` and can be useful,
for example when one particular instance runs out of control.
But as we don't include any information that allows to actually
distinguish between instances, multiple instances appear simply
as duplicated app entries.
Given that a menu is too limited for detailed information, stop
representing individual instances, and track apps instead.
https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/6654
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2790>
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