Cross domain impersonate

We usually login to the admin console on our own url (e.g. keycloak.mycompany.com) and we set a different frontend url for a specific realm (e.g. auth.myproject.com)

I’ve set these java opts

      -Dkeycloak.adminUrl=https://keycloak.mycompany.com
      -Dkeycloak.hostname.default.forceBackendUrlToFrontendUrl=true

and the problem is that when I click on impersonate in the admin console I get redirected to the login page in the realm domain (auth.myproject.com)

It seems impossible to impersonate a user on a realm which frontend url is different than the console admin url?