Keycloak 21 - login-status-iframe and session status check not working anymore

Hi all,
long time ago ( probably we were using keycloak 11 ) in my company we introduced the usage of the login-status-iframe: we added the iframe in each page of our secured applications in order to check and react everytime we detected that the keycloak session was expired or killed.
Now it seems that this is not happening any more ( i really don’t know when the problem occurred for the first time) … we tried to debug the code but it seems that we are not able anymore to detect any session change… could it be that we are not receiving back cookies from keycloak? we really don’t know how to solve it…
Do you have any suggestion? Is this only our problem?

Thanks in advance