Before version 0.11
We were able to declare in the global jenkins configuration a PodTemplate with containers.

Here an simple pipeline example that was working with a global PodTemplate with 0.10

stage("Example"){
      node("mypod"){
          container("golang"){
          sh '''
            echo "something"
          '''
        }
     }
}

With 0.11 we get an error:

org.jenkinsci.plugins.workflow.steps.MissingContextVariableException: Required context class org.csanchez.jenkins.plugins.kubernetes.pipeline.PodTemplateStep is missing

It is now (with 0.11) mandatory to have the PodTemplate and containers declare within the pipeline to be able to make the «container» step work again.