Nothing is displayed for the widget.
It is definitely enabled.
No console errors are logged (Chrome or Firefox)
JSON can be seen in the Network tab of Chrome or Firefox for a GET to https://jsd-widget.atlassian.com/api/embeddable/I_USED_MY_DATA_KEY_HERE/widget
Web page used for testing is minimal, i.e.
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Widget Test</title>
</head>
<body>
<script data-jsd-embedded data-key="I_USED_MY_DATA_KEY_HERE" data-base-url="https://jsd-widget.atlassian.com" src="https://jsd-widget.atlassian.com/assets/embed.js"></script>
</body>
</html>
Building on prior support cases:
A) this ticket -- widget is definitely enabled as per that page
that ticket -- There are no permissions in "atlassian-addons-project-access" role. But since I am using the default JSD set-up, I have not changed the permission scheme. If this is the cause, then JSD widget doesn't work out-of-the-box.
I am using the demo of the next-gen project JSD.