If a stage in a declarative pipeline has status NOT_EXECUTED, the Delivery Pipeline plugin is unable to render the view since the NOT_EXECUTED status is not mapped in se.diabol.jenkins.pipeline.domain.status.StatusType and an IllegalArgumentException is thrown:

Error while serving https://jenkins/job/Docker/view/my_pipeline/api/json
java.lang.IllegalArgumentException: No enum constant se.diabol.jenkins.pipeline.domain.status.StatusType.NOT_EXECUTED
    at java.lang.Enum.valueOf(Enum.java:238)
    at se.diabol.jenkins.pipeline.domain.status.StatusType.valueOf(StatusType.java:20)
    at se.diabol.jenkins.workflow.model.WorkflowStatus.statusType(WorkflowStatus.java:44)
    at se.diabol.jenkins.workflow.model.WorkflowStatus.of(WorkflowStatus.java:32)
    at se.diabol.jenkins.workflow.model.Task.resolveStageStatus(Task.java:153)
    at se.diabol.jenkins.workflow.model.Task.resolve(Task.java:126)
    at se.diabol.jenkins.workflow.model.Stage.resolveStageNodes(Stage.java:141)
    at se.diabol.jenkins.workflow.model.Stage.extractStages(Stage.java:124)
    at se.diabol.jenkins.workflow.model.Pipeline.resolve(Pipeline.java:120)
    at se.diabol.jenkins.workflow.WorkflowPipelineView.resolvePipeline(WorkflowPipelineView.java:350)
    at se.diabol.jenkins.workflow.WorkflowPipelineView.resolvePipelines(WorkflowPipelineView.java:343)
    at se.diabol.jenkins.workflow.WorkflowPipelineView.getPipelines(WorkflowPipelineView.java:217)
    at org.kohsuke.stapler.export.MethodProperty.getValue(MethodProperty.java:72)