**Deselect Filtered **
When using the object selector for the scenario there should be a de-select button that unchecks all the boxes in the currently visible window. If you have no search term and no custom/open/vanilla filtering then this should remove everything that can be. (I.E. White checks only, not gray).

Filter to Selected
Option for the search bar, show only objects that are currently selected in the list. Additive to the search or other filters