Not sure if this affects the docs:

---------- Forwarded message ---------
From: Anatolii Bazko <abazko@redhat.com>
Date: Tue, Jul 27, 2021 at 11:02 AM
Subject: [che-dev] Using the networking.k8s.io/v1 API
To: che developer discussions <che-dev@eclipse.org>

Hello.

Currently che-operator [1] and che-server [2] use the extensions/v1beta1 API to create Ingress objects. This API won't be available in Kubernetes v1.22 [3]. That's why we are moving to use networking.k8s.io/v1 API which is available since Kubernetes v1.19.

After that Eclipse Che will require minimum Kubernetes v1.19 which is the oldest maintainable version of Kubernetes
 
Issue to track [4]

[1] https://github.com/eclipse-che/che-operator/
[2] https://github.com/eclipse-che/che-server/
[3] https://kubernetes.io/docs/reference/using-api/deprecation-guide/#ingress-v122

[4] https://github.com/eclipse/che/issues/20019
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