I get results from Deezer in both the Artwork Downloader and the "Search Internet for Picture" context menu, always 1000X1000; the preview square always has a blank caption in Artwork Downloader, but shows "deezer" in the other. Phred, do you NEVER get a hit for deezer in "Search Internet.." when it does show up in Artwork Downloader?
MusicBee 3.4.7596 P
BTW the uncaptioned result in Artwork Downloader is indeed deezer, found an example where the color difference matched the captioned one in "Search.." even with all the other sites showing slightly different results.