Spotify has recently introduced a mini player for Windows and Mac users. So far, the Spotify app on computers only supports full window which is quite annoying. Every time while using other applications such as a web browser, to change songs or skip etc. the Spotify window should be opened.
The mini player works independently and can float in any window regardless of the application. Users can resize themselves, it can play videos, music and even podcasts. The mini player will also not interfere with the activities of other applications and it gives the user full control more efficiently.
This feature appears to be limited to Spotify Premium users only. To use it, make sure your subscription is active, open the Spotify app on Windows or macOS and press the small box icon above the large box next to the volume control.