This feature was listed in another post for feature requests, but that thread's been dead for a while.
There is a functionality regression between 4.x & 5.x - this is the ability to see the covers for all movies in the DB, so that the user can visually browse all movies by cover.
This is something of a 'make or break' feature for me - I'm actually going to go back to 4.x... Or perhaps theres a way to get this view that I'm just not seeing??
The prior feature post that may reflect this is "- thumbnail view (possibilites of cover display in grid must be improved for xMM 5.0)"