Spotify has an excellent mini-player available from its web player. It isn't currently available from the desktop client.
There is a workaround for this if you are using Chrome. I'll share my step-by-step instructions:
- Ensure you have the latest version of Chrome.
- Uninstall the Spotify Desktop Client.
- Open the Spotify Web Player.
- Click the Three Dots (...) menu in Chrome
- Select Save and Share
- Select Create Shortcut
- This will install Spotify as a web app, which looks and works the same as the desktop client.
- You can pin this to your dock.
The miniplayer now works from your new Spotify Web App.