I'm still have this problem. I have Flutter app - the same code for Web and Android. When I login by Google oAuth by browser everything works fine. I can login, than I can logout.
But if I do the same operation in mobile app on Android, I log in successfully, but when I want to log out I'm getting an error.
This is screen from DevTools.
- I log in by google Oauth.
- Then check account and session - it's ok
- Then I log out - getting 401 error
TL;DR
Developers are experiencing a problem with Google OAuth login on mobile. The login works fine, but logging out results in a 401 error. They are using the same code for web and Android. They have provided a screenshot from DevTools showing the error.