Multiple Tags ugly in Tag Panel

I started using multiple tags (eg. ARTIST or COMPOSER) after I got my first FLAC and while these are correctly shown in the file list (Artist1; Artist2) they aren't in the tag panel (Artist1\\Artist2). Especially for the COMPOSER field it is a problem.

A real life example: Queen, The Platinum Collection, Disc 3, Track 2, Under Pressure [Rah Mix]
file list: John Deacon; Brian May; Freddie Mercury; Roger Taylor; David Bowie
tag panel: John Deacon\\Brian May\\Freddie Mercury\\Roger Taylor\\David Bowie

Tag Panel should display the content just as the file list does and semicolon is the perfect limiter.

Thanks!

Mp3tag uses the separator string of two backslashes '\\' ...
to display the existence of multiple single values within a multi-value tag-field, ...
respectively uses '\\' to concatenate multiple single values into a multi-value string.

If there already exists a multi-value tag-field within the current tag, ...
then Mp3tag displays in the Tag-Panel and in the Listview the single values in one string, ...
as a list of single values, which are separated by the string '\\'.

This behaviour is built into the Tag Panel edit fields, ...
in the Listview you may have to set up the column definition for Composer to ...
value=$meta_sep(COMPOSER,'\\')
If you want to see a different separator character or string, ...
then you may change the separator as you like it, for example ...
value=$meta_sep(COMPOSER,'; ').

Note: $meta_sep is only for displaying purposes.
In a format string Mp3tag needs the separator '\\' to concatenate single values into a multi-value tag-field.

If there exists in the Mp3tag Listview column defintion the item "value=%COMPOSER%" ...
and a cell content string like ...
'John Deacon; Brian May; Freddie Mercury; Roger Taylor; David Bowie'
... then this is a single-value string showing a "flat list" text string ...
but this is not a multi-value content.

You can apply the action "Split fields by separator" ...
Field: COMPOSER
Separator: ;
... to convert the "flat-list" of single values content into a multi-value content.

Filter for multi-value in COMPOSER ...
NOT "$meta(COMPOSER,1)" IS ""

Check for meta tag-field ...
$iflonger($meta(COMPOSER,1),0,'IsMeta=TRUE','IsMeta=FALSE')

DD.20150727.1423.CEST