Hi, this issue is extremely annoying.
In order to link google home to third party services you usually need to go through web authentication, which means filling in login/password at vendor's website. Standard practice when logging in to websites is to send you an email with confirmation code, which you then need to paste in the login form.
Now here comes the issue - in order to get a said confirmation code you need to read the email, but as soon as you open email application, web browser of a google home app closes and the whole progress of logging is reset. At this point the only way to actually complete authorization is read an email on different device so that you don't close login form.
So steps to reproduce are:
1. Try to link google home with 3rd party service - this will bring up web browser login form
2. Switch active android application to something else
3. Switch back to google home app, that web browser is now closed
