I am implementing the authorization code flow for linking a user's account in our app with their Google account (https://developers.home.google.com/cloud-to-cloud/project/authorization). When choosing to add a smart home Action in either the Google Assistant or Google Home apps and being taken to the user's browser to complete the authorization steps we require the user to perform multi-factor authentication. MFA codes are sent to the user via email or SMS but when they go to their messages or email inbox and the browser is sent to the background it is terminated and they are unable to complete the authentication process. Is there a reason why Google Assistant/Home are terminating the browser and is there any way around it? If I open the authentication URL from the Chrome app or Google app and put it into the background it is not terminated (see screenshot below) so I'd like to understand the difference in behaviour with the browser launched by Google Assistant/Home app.
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