-e: as per title

-repro:
--open attached project
--select the "prefab preview test" in the project explorer
--see the assigned sprite in the preview at the bottom of the inspector
--assign a new sprite in the Sprite Renderer component of the prefab
--NOTICE the preview isn't updated
--deselect and reselect the prefab
--notice the preview shows the correct sprite now

*Note :
Getting this error as well "Destroying object "" is not allowed at this time.".