If you select the "Add a new {entity}" option from the autocomplete, it opens a dialog with an iframe to the entity creation form.  It's possible to browse to an external domain from here by clicking on a documentation link, which then gives you access to the header/footer.  Doing so crashes the iframe due to the content security policy in place.  We should probably convert all links in the entity creation form to target="_blank" to avoid navigation inside the iframe.