The thumbnails in the "All Media" editor for a store are paged with up to 20 on a page. You can click "Edit" and drag the thumbnails around to reorder them. But only among those 20 on that page. Can't move on to an earlier or later page. The cheapest solution IMO would be to allow us to increase the page size from 20 to just about any number. You could allow us to see thousands of these and not slow down most browsers. Even on mobile devices.
Thanks. Cheers.
