Your solution redwing it was good enough but it export all songs genres and only the first genre...for example
Bossa nova; Deep House; Downtempo; Electronic; Latin
it exports only bossa nova
two issues
first about 150 genres weren't in any song as first genre that's why them wasn't exported
You must have typed in <Genre> instead of <Genres> in the box.
and second because of exporting all songs genres i had a list of 110000
i had to make some duplicate clean with excel to keep just one value from each genre
Although using <send tags to clipboard> feature should work, probably it would be much easier using Library Reports command with that huge number of tracks.
- Install and enable Additional Tagging Tools plugin
- Select music library node in left navigator
- Tools> Tagging Tools> Library reports
- Select <unsaved tags> preset using dropdown menu
- Tick <Genre> only (<Genre> and <Genres> work the same with this plugin)
- Preview and export in a text file