We tired reproducing this on our side and noticed there's no horizontal scroll option available on the desktop app. You can use the arrows in the top right corner above the playlist section. If you can't see them on each value of the resolution settings, we can suggest you run a clean reinstall of the Spotify app on your device. Follow the instructions here to find out how to do this.
If that doesn't fix it, send us some screenshots of the whole window view. You can use the Insert Photos option in the post editor to upload images to your response. This way we can take a closer look at the issue.
If you have more questions - don't hesitate to reach out here again.