Collection for New Object? (Version 2.8) This is driving me batty!  When I create a new object, it appears in some collection, sometimes one that is hidden, so I have to go hunting for it, expanding each in turn until I find something that does not belong.

How do I control which Collection will be used for new objects?
New objects are always added to the active collection. To make a Collection active just click on its icon in the outliner to set it as the one new objects are added to.

The active collection is indicated in the Outliner while in View Layer mode by a transparent circle overlay over its icon