ARTIST Pics missing

this is not related to the new 1.8 version, but was already in the previous version: many Artists’ pics are totally missing when browsing my >1000 artist library by artist, is there something I can do or am I doing something wrong ? I said many, but I am afraid it’s quite a few dozens
Please help

The first thing to check is that not all of your albums for that Artist are “unidentified”. At least one of your albums by that artist has to be properly identified by Roon. That will help a lot actually. If all your albums are identified and recognized by Roon, but there is no Artist picture, you can add one manually. That is really all you can do. If there is no artist image it is because Allmusic (the database they use for images) does not have an image of that artist or because that artist is not identified properly.