Google IDP brokering logout

Hi,

Recently started using IDP brokering via google as option to authenticate users in our app.
Followed documentation Page Redirection, and it works - users can login to our app using their google accounts.

Scenario:
Step 1 - user with google account used it to login to our app
Step 2 - some time later he signed out from his google account

Question:
How to make sign out from google by user to trigger termination of user session in keycloak / redirect him to app logout?