Tag field "user1"

I have a "User 1" tag field in my software. Is there a way to see this and edit this tag field in MP3TAG? Any help is appreciated. TIA

Do you see it via View → Extended Tags...?

No, I do not. I was curious if we could add the field manually.

Maybe, I should move my data from the "user 1" field to another that does show in MP3TAG?

It's most likely not stored in the metadata of the file itself then. Instead, your software might use an internal database for such fields.

If you want to be sure, I've sent you a link to a private upload location where you can upload a file for further analysis.

What file do you need?

The file which has the "user 1" field, which doesn't show in Mp3tag.

So should I backup my software, (XML file), and upload that?

No, I guess I misunderstood you. If you already know the field is not written to the actual metadata (tag) of the audio file, then you best move the data from the "user 1" field to another that does show in Mp3tag.