We've set up a few new issue types and added icons to these. The icons for the "standard" Jira issues work without problems but the icons for the new issue types only print the following as the image URL within the img tag:

$icons.get( $item.getElementValue('type') )

So apparently Confluence or Jira isn't evaluating something. This isn't critical but makes for ugly printouts from the macro due to lots of broken images if the issue type is shown.