I have seen this idea posted several times over the years and they are all marked closed. I personally find it really frustrating that people have clearly been asking for this and over and over been denied, especially because it seems like a rather simple feature. Anyway, on the web player on Chromebook, there is an excellent popout player that remains on top of other tabs and windows you open, has the album/song art and has simple controls like pause, play, skip, and rewind that show when you hover over it. You can also move it around your screen so you position it where is easiest for you. It's crazy to me that this feature hasn't been implemented already for the desktop application, or if it has then the fact that it's been removed. It's super annoying to have to stop what I'm in the middle of to open the Spotify window just to see what is playing, or to skip or save a song. Something with just the basics of these features would make a huge difference and make usability so much easier.