Fair point and thanks for your feedback! I have added an option to download a HTML file that you can open and use locally. That way you can be sure that the code does not change and you are always using the correct encryption. ;) Let me know if it works for you.

stacks

bitcoin

Verifiably secure dead drop to share bitcoin addresses and other secrets

I recommend using cryptomator over relying on sandboxed remote code execution as a feature (javascript) to encrypt your stuff. Yes you can verify it, but you have to verify it every time you reload the browser.

The good news is, the code you've already written can still be adapted into an app. Just loaded locally rather than from a webserver every time you refresh the page. 

As of right now, I would personally basically consider your site to be a honeypot that is trying to rely on time to relax a userbase before changing out the code one day. Nothing personal.