merge tags/genres meta data from several books?

[wjBLqf-_9]

I am cleaning up my library.

I have duplicates of things, except some duplicates have better meta data (tags/genres) than other duplicates.

It would be handy if there was some way to select all duplicates of one book, right click > edit metadata > merge metadata > let you pick which metadata to merge (I would pick tags/genres)

Then perform the merge... to all copies.

So I can then decide which of duplicate I keep.

Sort of similar to how I remember Windows 7 handled duplicate copies
...(disclaimer: I did say 'sort of' and 'similar' so this not a 1for1 citation from memory)
...If you ever used Windows 7 and copied a bunch of files to a folder with files of the same name... Windows 7 used to give you this "difference" window you could decide for each file (or click the nuke'em'all button).