When searching for a match from a tag source, you can click on the album art to open it in your default image viewer. Can this feature also be added to the Extended Tags dialog? Currently the image has to be right clicked and saved, or drag+dropped into a folder, and then launched.
You can also double-click on the cover display area in the tag panel to see it in a larger separate window.
I always keep the tag panel disabled, I didn't know that was there!