We want to shield users from being overloaded by an overwhelming stream
of notification banners, either due to coming back from idle/lock or
because an application is misbehaving. Previously we replaced all queued
notifications with a summary notification in that case, but now that
notifications appear in the summary immediately, we can simply stop
adding them to the queue and rely on the date menu to convey that
information to the user.
https://bugzilla.gnome.org/show_bug.cgi?id=744850
8c72c93aae