- The "extraArgs" component construct is now a list of "name"/"value" pairs instead of a string/string map. This has been done to support duplicate args where needed.
  - The "JoinConfiguration.discovery.timeout" field has been replaced by "JoinConfiguration.timeouts.discovery".
  - The "ClusterConfiguration.timeoutForControlPlane" field has been replaced by "{Init|Join}Configuration.timeouts.controlPlaneComponentHealthCheck".

- Kubeadm: default the kubeadm configuration to the containerd socket (Unix: `unix:///var/run/containerd/containerd.sock`, Windows: `npipe:////./pipe/containerd-containerd`) instead of the one for Docker. If the `Init|JoinConfiguration.nodeRegistration.criSocket` field is empty during cluster creation and multiple sockets are found on the host always throw an error and ask the user to specify which one to use by setting the value in the field. Make sure you update any kubeadm...

- Kubeadm: fixed a regression where the JoinConfiguration.discovery.timeout was no longer respected and the value was always hardcoded to "5m" (5 minutes). ([#125481](https://github.com/kubernetes/kubernetes/pull/125481), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]