We started tracking all windows to make sure the assumption that any
window can be match to an app holds. It is not expected however to
ever represent OR windows in the UI, so it seems better to exclude
them from get_windows() instead of expecting everyone to filter the
return value themselves.
(The returned list still includes "uninteresting" windows like attached
dialogs, which can be important for cases like the correct MRU order in
alt-tab)
https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/5233
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2252>
c02ca54943