@aamasri/popup NPM

Download & copy this package's "dist" folder into your web server's public folder eg. public/js/dist/*.
Rename "dist" to "popup" eg. public/js/popup
Load the popup script at the end of your web page (before the closing body tag) like this:

<body>
    ...

    <script src="/js/popup/popup.mjs"></script>
</body>
</html>

When the browser loads, popup will be attached to the browser's global window object. Use it anywhere in your scripts like this:

<button>Target</button>

<script>
    popup.open();          // Display the popup cheat sheet

    ...

    popup.closeLast();     // close the on-top popup
    
    ...
    
    popup.closeAll();

</script>

Then import and use it in your project's ES6 modules:

function helloWorld() { popup.open({ title: 'Greetings', source: 'Hello World' }); }

Popup supports npm under the name @aamasri/popup.