Hello,
I don't know if this is a bug or what. But, just to let you know, I noticed that when tagging a single track release, in the results window you can not see the tracklist for Discogs data (left column). I have to mention that I haven't checked others, because I only use Discogs data to tag music.
So, then, you have to open Discogs' release page to check track data like title/artist and tracklenght in case Discogs provides it.
This is a bug, and it is not a Discogs-WSS specific one, because you can also reproduce it with the Musicbrainz-WS. And you don't get all information from the album tab, because it doesn't contain the length of the track.
You have to distinguish between the field LENGTH and the file property _LENGTH.
The field LENGTH does not make sense IMHO although it is a valid ID3 tag field as you can write any value into that field, even text. The property _LENGTH written during the encoding does not change and cannot be edited in and by MP3tag.
At first sight, it looks as the upper left "Metadata Title" and the lower left "Tracks" remains empty.
But if you write this info into the tags of your file, you get this tags filled, including the track TITLE, ARTIST, ALBUM, TRACK and some more tags:
It is not as easy to check with 1-Track-Releases, wheter the local track has really the same length as the one from the online result.
And it could theoretically be that the returned result is even for another track TITLE.
I'm extracting two different parts from the discussion:
The result when querying Tag Sources for single releases is missing an entry for the track length in the tracks list. ā This is the bug and I'll fix this by adding a corresponding entry to the tracks list.
The result doesn't show the Title and Track# in the Title metadata list, which makes it more difficult than necessary to check if it's the correct title (scrolling the Album metadata list is needed instead, where the fields are to be found). ā I'll add Track# and Title (if available) to the list of Title metadata.