How to enable legacy-logout-redirect-uri

I am in the process of upgrading Keycloak from 11.0.3 to 17.0.1.

I have a legacy application that does not provide the logout endpoint with the ‘post_logout_redirect_uri’ and ‘id_token_hint’ parameters (it uses the legacy ‘redirect_uri’ parameter). Keycloak issues the following warning message:

Parameter ‘redirect_uri’ no longer supported. Please use ‘post_logout_redirect_uri’ with ‘id_token_hint’ for this endpoint. Alternatively you can enable backwards compatibility option ‘legacy-logout-redirect-uri’ of oidc login protocol in the server configuration.

Can someone provide me with the exact command line switch that I must provide to “kc.sh start …” in order to enable this feature?

Thanks,