Interacting with Confluence from JIRA - wiki vs storage

[Jesper Jakobsen]

I have been testing JIRAs abilities to add pages on Confluence using this guide:
https://scriptrunner.adaptavist.com/latest/jira/interacting-with-confluence-from-jira.html

My content for the body of the page is taken from a custom field which is rendered in wiki style. 

The first part the guide uses wiki as representation:

body : [
   storage: [
      value : pageBody,
      representation: "wiki"
   ],
],

But when the guide makes the XML to add the link back to the JIRA ticket then the representation is changed to storage:

body : [
   storage: [
      value : writer.toString(),
      representation: "storage"
   ]
]

When the Confluence page is created the link back is created as it should, but my text from the custom field is just placed as a single line, not even line breakers are added. 

How do I make the link back to the issue and make the body text format correct as it is in the wiki-style custom field?