M4b in Audio tags plug in unchanged?

[Leo]

The change only affects file display columns (and info-tips, rename, script objects, and other read-only uses of metadata; not the metadata editor).

M4b files and the metadata pane

We're adding M4B support for file display columns in the next update. I'm hesitant to add it as an alias for the metadata panel (i.e. as read-write, not just read-only) because I think there are some differences between M4A and M4B files, or at leas…