Behaviours sometimes don't work for full screen create/edit issue dialogs

We should test that behaviours work not only in a dialog window but in full screen mode as well (for example when you open it in a new tab)

There's a timing issue with the full screen create issue window, where behaviours are sometimes not applied.

You can reproduce this by setting up a any behaviour then opening the create issue dialog in a new window, click next and the behaviours aren't applied to the form.

This seems especially to happen in JIRA 7.3.x, though it could plausibly happen in earlier versions of JIRA 7.