Cannot Show Popup With Jquery Mobile 1.3.1

I'm trying to pop up a very simple 'are you sure?' popup in jQuery Mobile. But if I use the data-rel='popup' on the button, nothing happens. If I remove the data-rel it opens - but

Solution 1:

Place popup inside <div data-role=page> and that div should be the direct parent of popup div. I placed before <div data-role=content> in the below demo.

Demo

Dialog should be placed outside <div data-role=page> because they are treated as a page.