I'm trying to set up Spotify as a music service for Google Assistant on a Pixel 2.

After selecting Spotify in the music service settings, logging in, and confirming that I want to give Google access to my Spotify account, I'm being shown an empty page with the URL `https://clients3.google.com/cast/auth/3p/done?status=error`.

This suggests there has been some error, as indeed Spotify still shows as not linked in the Assistant settings. In my Spotify settings, however, Google is now authorized in the apps section. De-authorizing Google and retrying did not work.

Does anyone know how to fix this problem or work around it? Are there alternative methods to connect Spotify to the Assistant?