Playbooks can be viewed as YAML in a text viewer as well. 


After having opened an existing Playbook from the left side panel, or having created a new Playbook using Visual Editor, you can open the text viewer window by clicking on the left most icon on the top left side as shown below.


You should now see the visual editor window split into two, with a YAML text of the Playbook available for viewing on the right side of the split screen, along with the visual editor.