The prompt works when the 'Frameworks & Extensions' is set to jQuery 2.0.2 but when I add...
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.2/jquery.min.js"></script>
...to replace JSFiddle's jQuery 2.0.2 and I set 'Frameworks & Extensions' back to 'No-Library (pure JS)' the prompt does not work anymore.
After trying dozens of variations the prompt still fails to run. What is causing this difference in behavior?
This happens due to the way JSFiddle "inserts" the code in the output page.
Your fiddle uses 4 ways to input code:
The output part (bottom right) will print what you place on the above boxes like this:
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title> - jsFiddle demo by Birdlaw</title>
<!-- Here goes the selected JS lib (jQuery 2.0.2 in your example) -->
<!-- Selected Extensions are here (in your case, bootstrap, then bootbox) -->
<style type="text/css">
<!-- Content of the CSS (top right) box goes here -->
</style>
<script type="text/javascript">//<![CDATA[
$(window).load(function(){
//<!-- Content of the JavaScript (bottom left) box goes here -->
//<!-- Actually, this can be configured (the second combo at left menu - "onLoad") -->
});//]]>
</script>
</head>
<body>
<!-- Content of the HTML box goes here -->
</body>
</html>
As you can see, taking jQuery out of the selected framework and placing it in the HTML box has different outcomes.
Selecting it as framework places it before the Extension (bootstrap and bootbox) files. When it is in the HTML box, it is placed after the Extension files, thus yielding the error (because those files need jQuery).
How to make it work? If you want to place jQuery in the HTML box "manually", then place all of the Extensions files there as well, in the correct order. This will make it work as expected.
Here's an updated fiddle, containing the fix above.