[Request] Add a way to merge libraries

[Jonatan Nyberg]

I have many libraries that I would want to merge and use custom columns instead to sort them, it is problematic to move from one library to another when it is not possible to have many open at the same time to see which books you want to move and which already exist in the other library. I would also like that my added custom columns could be copied from one library to another and library settings if it is possible? When I was think about how I would like this to work, I came to think about the review downloaded metadata window, and something similar would be nice when the same book exist in both libraries but you want specify what settings/book details you want to be moved to the new library. So if the book already exist in the library you want to copy the book to, it would be possible to select which book details/library settings you want to merged with the new library and not copy the book.

[Kovid Goyal (kovid)]

The Fond duplicates plugin allows you to check multiple libraries for
duplicates. And you can use copy to library to copy or move multiple
books at once.

 status wontfix