URL description (MP3/WWW field/WXXX frame) is forced to uppercase

[ohrenkino]

By default any field name is upper case only.
If you need a different case, then set the desired case in the file userfields.ini.
See also here:

Copying data from extended tag (catalognumber) to custom tag (CATALOG)

Thank you - but is there a way to create the custom tag called Catalog to use in the action? I can for example in SAM Broadcaster edit the tag and save it (on an individual file) then see it in Music Brainz but cannot see that tag in MP3TAG or select it from the dropdown when creating the action. (I have found CATALOG does not work in SAM Broadcaster either, it has to be Catalog for it to pick it up) Many thanks.