mp4 files in Meta panel

[muso]

I'm not sure if this should be a bug report, or maybe I just got a setting wrong...

I tested with an mp3 file and an mp4 file, with their ID3 metadata made exactly the same in Mp3tag. In xyplorer, all that data can be shown in columns and in customised info tips, for both mp3 and mp4 files.

But in the Meta tab of the info panel, for the mp3 files some (not all) of the usual media fields appear, and for mp4 files only the Length and Comments are shown - not even the Title or Artists (aka Authors) appear there.

Did I get a setting wrong somewhere?