I’ve been having trouble with correcting wrong album art Roon imposed upon my library every now and then. I don’t know why Rood does this. Could I have an answer? It is also a baffling decision to get rid of scroll bar from ADD IMAGE menu. I have a rather large library and changing album cover is a nightmare. Would you please care to restore it?
If you’re running Roon on a Windows PC, then a workaround here is to use the Windows File Explorer to locate the image you want and then drag and drop it onto the “Add an image” splash screen. I think this will also work in a similar manner for Macs as well.
As for why some covers get replaced, check to see your import setting. If you have “Prefer best” set, then if Roon’s database gets updated with a higher resolution cover art image than what you have used locally, then the Roon image will be used and overwrite your local image.