GObject automatically notifies when passing properties as part of g_object_new(). This happens after the instance is created, thus after constructed(). By passing G_PARAM_EXPLICIT_NOTIFY, we avoid this behavior. However, we are still notifying PROP_CONTEXT in GcalWindow. Removing this other notify fixes the crashes related to GcalContext. https://gitlab.gnome.org/GNOME/gnome-calendar/issues/417