Has anyone had this problem of late.
I've only just discovered that it no longer shows up in iTunes.
Wrting to the %contentgroup% TAG is no longer viable.
Using iTunes 126.96.36.199 and mp3tag 2.79.
Looks like they discontinued File tag support for the existing Grouping field:
Now I've nowhere to write the PUBLISHERs info as I use the COMMENT field exclusively for songs key and mixed in key info.
If you write your tags to the %contentgroup% field then it displays in the work field in itunes (the only way currently to display this is by showing the column for it. And vise-Versa, if you write info to the work field it is now mapped to the %contentgroup% one.
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