The new section should be inserted into the bottom of Domain mapping using the Administrator perspective -
https://docs.openshift.com/serverless/1.30/knative-serving/config-custom-domains/domain-mapping-odc-admin.html

The draft documentation is below:

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Title: Overriding system deployment configurations

When specifying net-kourier for Ingress and using DomainMapping, the TLS for OpenShift Route is set to passthrough, and TLS is handled by Kourier Gateway. In such cases, there might be a need to restrict the allowed TLS cipher suite for users.

This section explains how to specify cipher suites for Kourier.

KnativeServing CR example

spec:
  config:
    kourier:
      cipher-suites: ECDHE-ECDSA-AES128-GCM-SHA256,ECDHE-ECDSA-CHACHA20-POLY1305  # *1.

*1. Specify the cipher suites to enable. It is also possible to specify multiple suites, separated by commas.

The Kourier Gateway's container image utilizes the ServiceMesh proxy image, and the default enabled cipher suites depend on the version of the ServiceMesh proxy.
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