How do I know what Music Library my Music App is Connected to?

[Hrothgar]

So, I just learned that I can have my Music app connect to different Music libraries by holding down the Option key when I start the app. But I can't seem to figure out what library its attached to unless I make a change to the data and then see which file updated. Is this something I can see somewhere? (I'm not referring to the location of the music files themselves, but the music library file that keeps the list of files and metadata.)