Hello Frederic,
The configuration options for the community operator when it comes to external domains is limited, but in your case where the cluster domain is mydomain.fr, you could configure it in your operator installation either with your values.yaml file that you use for the helm installation of the operator:
operator:
extraEnvs:
- name: CLUSTER_DOMAIN
value: mydomain.fr
or by setting this environment variable on your community operator deployment.
I hope this helps!