I created a prototype npm package that displays a popup for selected text on a website.

npm

https://www.npmjs.com/package/@nakamura196/text-popup

Source code

https://github.com/nakamura196/text-popup

Demo page

https://nakamura196.github.io/text-popup/

The following article was used as a reference for development.

https://zenn.dev/nino_cast/articles/98a0a87f58026f

You can try it by adding the following two lines to your website.

<<ssccrriipptt>strecx=t"Photptupps(:)/;/<c/dsnc.rjispdte>livr.net/npm/@nakamura196/text-popup/dist/main.min.js"></script>

I hope this is helpful as a reference for developing and publishing npm libraries.