Went through this situation where I migrated the server and of course the posters would not display correctly after moving the library.
With 5000+ items in a library, the refresh all metadata would never complete the whole library.
How to refresh the metadata for a whole batch of movies then ?
When you hover an item, you can select it by clicking the small round button in the upper left corner of the item.
THEN, drag your mouse cursor, clicked, over all the movies you want to select. It doesn’t have to be in one go, you can release the button, scroll, re select a batch more etc.
Once happy with your selection hit the 3 dots on the selection row that appeared on top the library and hit refresh metadata.
Way easier than having to do that item by item, might be useful to some.
So shift click selects a range of items, even faster.⅔
