macOS + Apple TV + Google Chrome

In the past, I was able to use Apple TV inside Google Chrome. But it stopped working

It turned out, you need to do some tweaking before it starts working again

1. On your computer, open Chrome.
2. At the top right, click More Settings .
3. Click Privacy and security. 
4. Click Third-party cookies. 
5. Click See all site data and permissions >  (It's near the bottom of the page)
6. At the top right, search for Apple.
7. To the right of Apple.com, click the Delete icon.
8. To confirm, click Delete.
9. Reload the Apple TV site and sign in.

source: https://discussions.apple.com/thread/255616880