Thanks for the suggestion and the link to the image so that I could better understand what window you were referring to. Well, floating window for lyrics is honestly quite a pain as it's always in the way.
I was about to write this: As for panel configuration, there's nothing really where to show lyrics in a click without taking space away from other panels. That's why I still think it would be good to either have a lyrics tab next to music explorer, now playing, etc. or integrate lyrics into the now playing tab.
But I've just found out this while writing this comment: I can set "lyrics" to be shown in "playing now" tab instead of "tracks playing". Problem solved. Thank you very much for your help