ansible: register block fail

gistfile1.txt

---
- name: Test
  hosts: localhost
  tasks:
    - name: test mode
      shell: echo 1
      register: env

    - debug: msg="{{ env.stdout }}"

    - block:
      - name: will never run
        shell: echo 2
        register: env set_when_task_skipped=false
      when: false
    
    - debug: msg="{{ env }}"