Issue with repeatable regions in templates?

I have a template I created with a repeatable region. In previous versions of Dreamweaver when I created an HTML page from the template file I was shown a dialogue box on the region which let me add and subtract repeatable regions. In Dreamweaver CC 2017 this dialogue box doesn't show up. If I click on the repeatable region I get an option in the Edit menu to Cut, Copy, or Delete the repeating region, but none of these commands appear to do anything, and Copy is not followed by an option to Paste.  Below is a bare-bones example that doesn't work as expected. Is there some new way to use repeatable regions or some setting I don't know about?

Thanks in advance.

<!doctype html>

<html><!-- InstanceBegin template="/Templates/test.dwt" codeOutsideHTMLIsLocked="false" -->

<head>

<meta charset="UTF-8">

<!-- InstanceBeginEditable name="doctitle" -->

<title>Untitled Document</title>

<!-- InstanceEndEditable -->

<!-- InstanceBeginEditable name="head" -->

<!-- InstanceEndEditable -->

</head>

<body>

<!-- InstanceBeginRepeat name="RepeatRegion1" --><!-- InstanceBeginRepeatEntry --><!-- InstanceBeginEditable name="EditRegion3" -->RepeatRegion1<!-- InstanceEndEditable --><!-- InstanceEndRepeatEntry --><!-- InstanceEndRepeat -->

</body>

<!-- InstanceEnd --></html>