How transfer tags' multiple values to new tags using an action?


I thought this would be straightforward but it wasn't.
I have an action (see screenshot) that copies the ARTIST field to ALBUMARTIST and ALBUM ARTIST. Now I have begun with multiple values in the artist field but when running the action only the first value is copied to the two other fields.

How can I get the action to copy all values?



Thanks for your reply!
Could you please elaborate, though, since I am not that well versed in title formatting.
Are these values I should enter into the definition of my action before the format values?

No. This is the content of the Action-file (*.mta) where your action is stored, when you save it.

If you want to create your action with the action-menue just take $meta_sep(artist,\\) instead of %artist% as format-string.